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Showing papers on "Intraperitoneal injection published in 1990"


Journal Article
TL;DR: It is demonstrated that TNF plays an important role in the early pathophysiologic alterations that occur after systemic exposure to LPS.
Abstract: Tumor necrosis factor-alpha (TNF) has been implicated strongly as a principal mediator in the pathogenesis of septic shock. The authors investigated the in vivo production of TNF in CBA/J and CD-1 mice that had been primed by an intraperitoneal injection of complete Freund's adjuvant followed 2 weeks later by an intraperitoneal injection of lipopolysaccharide (LPS). TNF bioactivity peaked in both the ascites and plasma one hour after challenge, and TNF mRNA expression in the ascites cells peaked 30 minutes after LPS. After the induction of bioactivity, an interstitial pulmonary neutrophilic infiltrate occurred that was quantitated both morphometrically and by a myeloperoxidase (MPO) assay. Peripheral blood neutrophilia and lymphopenia developed after the LPS injection (PMNs: control, 46 +/- 2%; LPS, 65 +/- 3%; Lymphs control, 53 +/- 2%; LPS, 37 +/- 3%). Treatment with dexamethasone (Dex) completely inhibited the pulmonary neutrophilic infiltrate as measured by the (MPO) assay. Because Dex will inhibit the production of several cytokines, anti-TNF antiserum was given to mice at the same time as the LPS challenge to assess specifically the role of TNF in inducing these changes. This antiserum partially blocked the pulmonary neutrophil infiltrate, and completely blocked the peripheral blood changes at one hour after LPS. These data demonstrate that TNF plays an important role in the early pathophysiologic alterations that occur after systemic exposure to LPS.

180 citations


Journal ArticleDOI
TL;DR: Although these tumors undoubtedly reflect infection of the transferred B cells with EBV in vivo, intraperitoneal transfer of short-term lymphoid cell lines transformed in vitro withEBV resulted in ascites production without evidence of tumor formation.
Abstract: C.B-17 scid mice were reconstituted by intraperitoneal injection of human tonsil cells or PBL from EBV-seronegative donors. Subsequent injection of EBV resulted in the rapid development (within 19-33 d) of aggressive, fatal, lymphoproliferative disorders of human B cell origin. Autopsies revealed solid tumors in the abdomen, and occasionally in the liver, thymus, or spleen. Histopathologic analysis showed that the tumors were high-grade immunoblastic lymphomas and FACS analyses of tumor cells indicated that they were of human B-lymphoid origin. The tumor cells grew in vitro and induced new tumors on injection into severe combined immunodeficient (SCID) mice. Karyotypic analysis and Southern blots for c-myc or bcl-2 rearrangements revealed no chromosomal abnormalities and translocations. Southern blot analysis also showed that the cells possessed EBV DNA sequences. Although these tumors undoubtedly reflect infection of the transferred B cells with EBV in vivo, intraperitoneal transfer of short-term lymphoid cell lines transformed in vitro with EBV resulted in ascites production without evidence of tumor formation.

166 citations


Journal ArticleDOI
TL;DR: It is demonstrated that the administration of excessive doses of arginine induces a new, noninvasive experimental model of acute necrotizing pancreatitis, and pancreatic architecture appeared almost normal after 14 days.
Abstract: We examined the biological and histologic characteristics of a new experimental model of acute necrotizing pancreatitis induced by excessive doses of arginine in rats. Rats were given a single intraperitoneal injection of 500 mg/100 g body weight of L-arginine. At 12-24 hr after the arginine injection, serum levels of amylase, lipase, and anionic trypsin(ogen) reached respective peak values 2, 5, and 20 times those of control rats without arginine and returned to control levels after 24-48 hr. The contents of pancreatic protein, DNA, and digestive enzymes were markedly reduced after the arginine injection and reached their nadirs at 72 hr. After 14 days these levels were almost normal. Histologic examination revealed a number of small vesicles within acinar cells at 6 hr, which were identified as markedly swollen mitochondria by the electron microscope. Other intracellular organelles and nuclei also showed degenerative changes. At 12 hr interstitial edema appeared, and acinar cell necrosis was seen after 24 hr. The extent and severity of necrotic changes of pancreatic exocrine tissue with inflammatory cell infiltration were maximal at 72 hr. At seven days, pancreatic acinar cells began to regenerate, and pancreatic architecture appeared almost normal after 14 days. The present study has demonstrated that the administration of excessive doses of arginine induces a new, noninvasive experimental model of acute necrotizing pancreatitis.

141 citations


Journal ArticleDOI
TL;DR: The apparent mechanism of action of L651582 is via inhibition of the receptor-mediated stimulation of effector enzymes utilizing guanine nucleotide-binding protein signal transduction, which thus makes L65 1582 a novel anticancer agent.
Abstract: L651582 (Merck Institute for Therapeutic Research, Rahway, NJ) is a novel carboxyamide-amino-imidazole compound originally developed as a coccidiostat (U.S. patent No. 4,590,201). We studied the inhibitory effects of this compound on cancer proliferation, adhesion, and motility in vitro and in vivo in a model of ovarian cancer progression. L651582 reversibly inhibited up to 60% of the autocrine motility factor-stimulated tumor cell motility and tumor cell adhesion to tissue culture plastic. Autocrine motility factor-stimulated phosphoinositide metabolism was reduced significantly by treatment of the cells with 3 microM L651582 (P = .022). Thymidine incorporation and clonogenic growth of A2058 human melanoma, MDA-MB-231 human breast cancer, OVCAR-3 human ovarian cancer, and 5R-transformed rat embryo fibroblast cell lines were inhibited 60%-80% by 1-10 microM L651582. Intraperitoneal injection of OVCAR-3 cells causes malignant ascites, peritoneal carcinomatosis, and serosal and visceral seeding that, if left untreated, are lethal to nude mice. Intraperitoneal L651582 markedly prolonged survival of nude mice heavily laden with ovarian cancer [mean survival time of treated group divided by mean survival time of control group = 220% (P less than .03)]. The apparent mechanism of action of L651582 is via inhibition of the receptor-mediated stimulation of effector enzymes utilizing guanine nucleotide-binding protein signal transduction, which thus makes L651582 a novel anticancer agent. L651582 should be considered for further clinical development.

133 citations


Journal ArticleDOI
TL;DR: The hypotheses that IL-1 beta is responsible for a significant part of LPS fever and that TNF acts as an endogenous antipyretic to limit the magnitude of L PS fever in the rat are supported.
Abstract: The roles of interleukin 1 beta (IL-1 beta) and tumor necrosis factor-alpha (TNF) in lipopolysaccharide (LPS)-induced fever were investigated in the rat. We used antisera against IL-1 beta and TNF to determine whether we could alter the fever by blocking the action of these cytokines. The intravenous injection of antiserum IL-1 beta 3.5 days before the intraperitoneal injection of LPS resulted in a mean fever that was significantly lower than that seen in rats that had been injected with control serum (0.36 +/- 0.11 vs. 0.82 +/- 0.16 degrees C, P = 0.016). The intravenous injection of antiserum against TNF 3.5 days before the intraperitoneal injection of LPS did not block the fever but significantly enhanced it (1.31 +/- 0.16 vs. 0.82 +/- 0.16 degrees C, P = 0.027). These data support the hypotheses that IL-1 beta is responsible for a significant part of LPS fever and that TNF acts as an endogenous antipyretic to limit the magnitude of LPS fever in the rat.

126 citations


Journal ArticleDOI
TL;DR: Experimental autoimmune hepatitis is a murine model of autoimmune hepatitis probably mediated by autoreactive T cells and will allow studies of the pathogenesis of autoimmune liver disease.

111 citations


Journal ArticleDOI
TL;DR: Data indicate that hCG can prevent both initiation and progression of mammary carcinogenesis by using the placental hormone human chorionic gonadotropin (hCG).
Abstract: The observation that mammary cancer induced by 7,12-dimethylbenz[a]anthracene (DMBA) in young, virgin, Sprague-Dawley rats is abolished by pregnancy led us to test the possibility of protecting the mammary gland from chemically induced carcinogenesis by using the placental hormone human chorionic gonadotropin (hCG). Fifty-day-old, outbred, virgin, Sprague-Dawley rats were utilized in two different experimental protocols. In protocol 1, four groups of virgin rats received either no hCG (group I) or a daily intraperitoneal injection of hCG at 1 IU (group II), 10 IU (group III), or 100 IU (group IV) for 21 days; group I and groups II-IV, at 21 days after the last injection, were given a single intragastric dose of 8 mg of DMBA per 100 g of body weight. In protocol 2, 50-day-old rats were treated with a single intragastric dose of 8 mg of DMBA per 100 g of body weight; 21 days later, they were separated into groups V and VI. Group V rats remained undisturbed, except for palpation twice a week for detection of tumor development. Group VI rats received a daily intraperitoneal injection of 100 IU of hCG for 60 days. Tumorigenesis was evaluated 24 and 30 weeks after carcinogen administration in animals in protocols 1 and 2, respectively. In protocol 1, in which animals (with the exception of the control group) were treated with hCG prior to carcinogen administration, the incidence of adenocarcinomas decreased in a dose-dependent manner, from 43.8% in the controls (group I) to 34.4%, 18.2%, and 6.15% in groups II-IV treated with 1, 10, or 100 IU of hCG, respectively. Among animals in protocol 2, hCG treatment significantly reduced the incidence of adenocarcinomas, from 100% in DMBA-treated rats (group V) to 45.5% in rats treated with DMBA plus hCG (group VI). These data indicate that hCG can prevent both initiation and progression of mammary carcinogenesis.

110 citations


Journal Article
TL;DR: The changes in complement and CR1 on E and in serum observed in these patients resembled those seen in patients with SLE: i.e., a reduction in CR1 and an increase in C3 and C4 on E, and reduced serum C.
Abstract: C and CR1 have been shown to participate in the clearance of injected, preformed, immune complexes in humans and in non-human primates. Their role in the physiologic disposal of immune complexes formed in vivo in humans was investigated in three patients receiving radioimmunotherapy for ovarian carcinoma. On day 0 each patient received, by intraperitoneal injection, 10 mg of 131I-mouse anti-tumor mAb (10 mCi/mg). On days 1 and 2, 18 mg of trace-labeled, 125I-human anti-mouse IgG was administered by i.v. infusion over 15 min, to accelerate the clearance of the 131I-anti-tumor antibody from the circulation and reduce the radiation dose to the marrow. Sequential blood samples were obtained after the injection of the second (anti-mouse) antibody, to monitor clearance. Immune complexes (shown by sucrose gradient centrifugation to be 19 to 40 S in size) formed within 5 min, and were cleared with a half-life of 11 +/- 1.7 min in the liver. Complexes were measured by 4% polyethylene glycol precipitation, and by solid phase C3d- and C1q-binding assays. Between 8 and 11% of the total available complexed material bound to CR1 on E. Peak binding of immune complexes to red cells occurred 10 min after the maximal complex load was detected by precipitation with polyethylene glycol. At that time, immune complexes bound to E constituted one-fifth of the total circulating pool of complexes. Coincident with immune complex formation and clearance, a 47% fall in serum C4, C3, and CH50 was measured, with the deposition of up to 1230 molecules of C4, and 2590 molecules of C3 on the surface of red cells. During 20 min after immune complex formation there was a mean loss of 32% of erythrocyte CR1. The changes in complement and CR1 on E and in serum observed in these patients resembled those seen in patients with SLE: i.e., a reduction in CR1 and an increase in C3 and C4 on E, and reduced serum C.

109 citations


Journal ArticleDOI
TL;DR: The results suggest that 6R‐BH4 has a dopamine‐releasing action, which is not dependent on biosynthesis of dopamine.
Abstract: We have previously reported that intracerebroventricular administration of 6R-L-erythro-5,6,7,8-tetrahydrobiopterin (6R-BH4), a cofactor for tyrosine hydroxylase, enhances biosynthesis of 3,4-dihydroxyphenylethylamine (dopamine) in the rat brain. In the present study, we have more precisely examined the effects of 6R-BH4 on dopamine release in vivo from the rat striatum using brain microdialysis. The amount of dopamine collected in striatal dialysates was determined using HPLC with electrochemical detection after purification with an alumina batch method. When the striatum was dialyzed with Ringer solution containing various concentrations of 6R-BH4 (0.25, 0.5, and 1.0 mM), dopamine levels in striatal dialysates increased in a concentration-dependent manner. Biopterin had little effect on dopamine levels in dialysates. The 6R-BH4-induced increase in dopamine levels in dialysates was abolished after pretreatment with tetrodotoxin (50 microM) added to the perfusion fluid, but after pretreatment with nomifensine (100 mg/kg, intraperitoneal injection), an inhibitor of dopamine uptake mechanism, a larger increase was observed. After inhibition of tyrosine hydroxylase by pretreatment with alpha-methyl-p-tyrosine (250 mg/kg, intraperitoneal injection), most of the increase persisted. These results suggest that 6R-BH4 has a dopamine-releasing action, which is not dependent on biosynthesis of dopamine.

99 citations


Journal ArticleDOI
Dolan Me1, Stine L1, Mitchell Rb1, Moschel Rc1, Anthony E. Pegg 
TL;DR: It is indicated that O6-benzylguanine is a suitable compound for use in experiments to examine the role of the alkyltransferase protein in vivo in counteracting the effects ofAlkylating agents.
Abstract: Experiments were carried out in mice and hamsters to determine whether the activity of the DNA repair protein, O6-alkylguanine-DNA alkyltransferase, in tissues and tumors was reduced by treatment with O6-benzylguanine in vivo. Following intraperitoneal injection of O6-benzylguanine, there was a rapid and complete loss of alkyltransferase activity in both livers and kidneys of mice and hamsters. The activity in mouse tissues was slowly restored, reaching pretreatment activities at 16 hr and 72 hr after injection of O6-benzylguanine at 10 mg/kg or 126 mg/kg, respectively. The activity in hamster liver was restored at a significantly lower rate, reaching less than 20% pretreatment activity 72 hr after treatment with 100 mg/kg of O6-benzylguanine. The efficient reduction of alkyltransferase activity by O6-benzylguanine was in sharp contrast to the inability of O6-methylguanine to bring about similar reductions. Activities dropped to about 55% of pretreatment activities in several mouse organs 4 hr after treatment with 126 mg/kg of O6-methylguanine compared to a more than 90% reduction in activity in animals after treatment with O6-benzylguanine. The sensitivity of SF767 cells to meCCNU after treatment with O6-benzylguanine was increased substantially. Furthermore, treatment of nude mice carrying SF767 tumor with 60 mg/kg of O6-benzylguanine prior to either 7.5 or 15 mg/kg of meCCNU led to significant inhibition of tumor growth. These studies indicate that O6-benzylguanine is a suitable compound for use in experiments to examine the role of the alkyltransferase protein in vivo in counteracting the effects of alkylating agents.(ABSTRACT TRUNCATED AT 250 WORDS)

95 citations


Journal ArticleDOI
TL;DR: In this paper, the authors attempted to transplant normal allogeneic hepatocytes into the Watanabe heritable hyperlipidemic (WHHL) rabbit without chronic immunosuppression to cure the LDL receptor-deficient state.
Abstract: The Watanabe heritable hyperlipidemic (WHHL) rabbit reproduces human familial hypercholesterolemia due to a congenital low-density lipoprotein receptor deficiency and is characterized by elevated serum LDL cholesterol levels and early atherosclerosis. We attempted to transplant normal allogeneic hepatocytes into WHHL rabbits without chronic immunosuppression to cure the LDL receptor-deficient state. Livers from normal New Zealand White (NZW) rabbits were digested by intraportal perfusion of collagenase solution. Pure hepatocytes (PH) were obtained by Percoll gradient separation and nonparenchymal (NP) liver cells by pronase digestion. PH and NP were incubated with fluorescein isothiocyanate-monoclonal anti-rabbit class I, anti-class II, and anti-T cell antibodies and subjected to flow cytometry analysis. PH and NP were also used as stimulators in one way mixed lymphocyte-hepatocyte cultures (MLHC), before and after ultraviolet B light (UVB) exposure. Intraportal and intrasplenic injection of allogeneic PH were also performed in homozygous WHHL rabbits. PH were attached to collagen-coated dextran microcarriers (mc-PH) for intraperitoneal injection. Recipient control and transplanted WHHL rabbits received a single dose of cyclosporine subcutaneously (10 mg/kg/s.c.) at the time of transplantation. PH were mainly class I-positive (77.6%) and class II-negative (5.9%), while 31.5% of NP cells were class II-positive. In MLHC, PH did not stimulate proliferation, (stimulation index: 0.97 +/- 0.21), unlike NP (SI: 23.7). This latter response was abrogated by prior exposure of NP to UVB light. Intraportal injection of PH (n = 4) reduced serum LDL cholesterol to 60% of baseline, an effect lasting 2-3 weeks, and dose-dependent. Intraperitoneal mc-PH, 4 x 10(8) (n = 4), reduced serum LDL cholesterol levels to 45% of baseline more than 4 weeks posttransplant (P = 0.04). We conclude that transplantation of normal allogeneic NZW rabbit mc-PH reduces serum LDL cholesterol levels in homozygous WHHL rabbits without chronic immunosuppression. Longitudinal studies will establish if less atherosclerosis develops in mc-PH WHHL recipients than sham controls.

Journal ArticleDOI
01 Dec 1990-Blood
TL;DR: The relationship between the oral efficacy and the acute toxicity of hydroxypyridin-4-one iron chelators has been investigated to clarify structure-function relationships of these compounds in vivo and to identify compounds with the maximum therapeutic safety margin.

Journal ArticleDOI
15 Dec 1990-Blood
TL;DR: The data suggest that the thrombocytosis induced by IL-1 beta is mediated by IL -6 or a combination of IL-6 and other cytokine(s), and that IL- 6 may play a regulatory role in platelet production in vivo.

Journal ArticleDOI
TL;DR: A single intraperitoneal injection of complete Freund's adjuvant in diabetes-prone BB/Wor rats between 9 and 28 years of age reduced the incidence of diabetes at 120 days from 89% to 10-28%, whereas injection of CFA after 40 days of age was ineffective.

Journal ArticleDOI
TL;DR: Protection against O2 toxicity by TNF insufflation was associated with increased lung superoxide dismutase, catalase, and glutathione peroxidase activities and the enhancement of lung antioxidant enzyme activities was noted at 55 h of O2 exposure, which suggests that TNF-induced increase in antioxidants enzyme activities contributes, at least in part, to the observed protection.
Abstract: Tracheal insufflation of tumor necrosis factor (TNF; 5 micrograms or 1.2 x 10(5) U) markedly enhanced the survival of adult rats exposed to 100% O2: 12 of 17 rats (71%) survived for greater than 11 days, whereas 30 of 30 control (Hanks' balanced salt solution) insufflated rats (100%) died within 3 days of O2 exposure. Insufflation of gamma-interferon (5 micrograms) or intraperitoneal injection of up to 40 micrograms TNF did not afford any protection. At 55 h after O2 exposure, TNF-insufflated rats showed less pulmonary edema, as determined by the extravascular lung water content-to-bloodless lung dry weigh ratio and less alveolar capillary leak as determined by the protein content in the bronchoalveolar lavage fluid, than control insufflated rats similarly exposed. This protection against O2 toxicity by TNF insufflation was associated with increased lung superoxide dismutase, catalase, and glutathione peroxidase activities. The enhancement of lung antioxidant enzyme activities was noted at 55 h of O2 exposure, when control animals began to die of O2 toxicity. This temporal relationship suggests that TNF-induced increase in antioxidant enzyme activities contributes, at least in part, to the observed protection.

Journal ArticleDOI
TL;DR: The results suggest that formosanin-C might display antitumor activity in association with modification of the immune system.

Journal ArticleDOI
TL;DR: It is suggested that immunization with a LIS extract or whole cells may induce a protective response against experimental B. gingivalis infection.
Abstract: The effects of immunization in modulating the pathogenesis of Bacteroides (Porphyromonas) gingivalis infection in a murine model system were examined. BALB/c mice were immunized by intraperitoneal injection with B. gingivalis ATCC 53977 (one injection per week for 3 weeks), or with a lithium diiodosalicylate (LIS) extract (one injection per week for 3 weeks), or with lipopolysaccharide (LPS; one intravenous or intraperitoneal injection) from this same strain. Two weeks after the final immunization, the mice were challenged by subcutaneous injection of B. gingivalis ATCC 53977. Mice immunized with bacteria had no secondary lesions and no septicemia, whereas mice immunized with LIS extract had few secondary lesions and no septicemia. Mice immunized with LPS and nonimmunized mice demonstrated secondary abdominal lesions and septicemia after challenge. Bacterial cells and LIS extract, but not LPS, induced serum antibody and antigen reactive lymphocytes, as measured by enzyme-linked immunosorbent assay, immunoblot, Western immunoblot transfer, and in vitro lymphoproliferative responses. The present study suggests that immunization with a LIS extract or whole cells may induce a protective response against experimental B. gingivalis infection.

Journal ArticleDOI
TL;DR: The role of tumor necrosis factor (TNF, cachectin), a putative endogenous pyrogen, was investigated by comparing fever and plasma TNF levels after the intraperitoneal and intramuscular injection of 10 micrograms/kg lipopolysaccharide into male Sprague-Dawley rats and by neutralization of endogenous TNF using TNF antiserum.
Abstract: The role of tumor necrosis factor (TNF, cachectin), a putative endogenous pyrogen, was investigated by comparing fever and plasma TNF levels after the intraperitoneal and intramuscular injection of 10 micrograms/kg lipopolysaccharide (LPS) into male Sprague-Dawley rats and by neutralization of endogenous TNF using TNF antiserum. An intraperitoneal injection of LPS caused a biphasic fever that lasted approximately 6.5 h. TNF levels in these rats peaked at 657 +/- 222 U/ml at 1 h then declined to virtually undetectable levels by the fourth hour. The intramuscularly injected animals showed a lower monophasic fever and low sustained TNF levels (40 +/- 10 U/ml at 1 h, 18 +/- 11 U/ml at 4 h). In a second study, an antiserum that had been shown to neutralize rat TNF was injected intraperitoneally 2 h before the intramuscular injection of 10 micrograms/kg LPS. Control rats were injected with normal rabbit serum before LPS. During the second hour after the injection of LPS, the animals that received the antiserum developed fevers that tended to be lower than those seen in the rats that were injected with control serum (0.33 +/- 0.06 vs. 0.58 +/- 0.1), although this difference was not significant. However, during the third through eighth hours after LPS, the antiserum-injected rats had mean body temperatures that were significantly higher than those of the control rats (1.62 +/- 0.11 vs. 1.07 +/- 0.09; P = 0.0005).(ABSTRACT TRUNCATED AT 250 WORDS)

Journal ArticleDOI
TL;DR: Gentamicin entrapped within stable multilamellar liposomes was used to treat mice after they were infected per os with Salmonella dublin and confirmed that gentamicin in liposome is less toxic in mice than is free gentamicIn and is extremely effective therapy for disseminated Salmonellae infections in mice.
Abstract: Gentamicin entrapped within stable multilamellar liposomes was used to treat mice after they were infected per os with Salmonella dublin. Of 10 mice, 8 survived after a single intravenous (i.v.) injection of 2 mg of gentamicin liposomes per kg compared with 0 of 10 treated with the same amount of free gentamicin. All mice survived after treatment with a single i.v. or intraperitoneal injection of 20 mg of gentamicin liposomes per kg, whereas that dose of free drug was completely ineffective and caused neuromuscular paralysis when injected rapidly i.v. In mice treated with gentamicin liposomes, there was a steady decrease in the number of salmonellae in spleens for 2 weeks after treatment. High concentrations of gentamicin were present in the spleen for at least 10 days after treatment. Although gentamicin was not detected in the mesenteric lymph nodes of mice treated with gentamicin liposomes, bacterial counts in the nodes also decreased over time. Small numbers of bacteria remained viable in the mesenteric lymph nodes and Peyer's patches but not in the spleens of mice treated with 20 to 80 mg/kg. Mice treated with doses of gentamicin liposomes as high as 80 mg/kg showed only a transient increase in blood urea nitrogen and no rise in serum creatinine. These results confirm that gentamicin in liposomes is less toxic in mice than is free gentamicin and is extremely effective therapy for disseminated Salmonella infections in mice.

Journal ArticleDOI
TL;DR: A significant blood glucose concentration dependent increase of glycosylation in newly synthesized collagen in hyperglycemic animals that is associated with increased collagenase activity and decreased wound collagen content is demonstrated.

Journal Article
TL;DR: It is concluded that N-Ac-4-S-CAP is a suitable model for developing chemotherapy to treat melanoma characterized by high tyrosinase activity and melanin synthesis.
Abstract: A phenolic amine compound, 4-S-cysteaminylphenol (4-S-CAP), is a potent depigmenting agent. To develop more efficacious antimelanoma agents, we synthesized four homologues of 4-S-CAP: N-acetyl-4-S-CAP (N-Ac-4-S-CAP), alpha-methyl-4-S-CAP, 4-S-homo-CAP, and N,N'-dimethyl-4-S-CAP. We tested these five compounds in mice in vivo. After s.c. or i.p. injection of saline solution (in control groups) or one of the compounds, follicular melanocytes were examined by light and electron microscopy to assess the degree of melanocytotoxicity; N-Ac-4-S-CAP induced the most depigmentation (98%), whether given i.p. or s.c. After injection of 4-S-CAP or N-Ac-4-S-CAP, the number of murine B16F10 melanoma colonies formed in the lungs was determined; 4-S-CAP and N-Ac-4-S-CAP were almost equally effective, reducing the colonies to 32 and 25% of mean control, respectively. Metabolic studies of the urine showed 9% of 4-S-CAP and 20% of N-Ac-4-S-CAP injected i.p. were excreted unchanged in 24 h; 1.3% of the N-Ac-4-S-CAP was excreted as 4-S-CAP, indicating some conversion. We conclude that N-Ac-4-S-CAP is a suitable model for developing chemotherapy to treat melanoma characterized by high tyrosinase activity and melanin synthesis.

Journal ArticleDOI
TL;DR: It was concluded that interleukin-1 activates the sympathetic nerves specifically in the spleen and lung and is responsible for changes in norepinephrine turnover in rats after intraperitoneal injection of recombinant human interleukoethanol beta.

Journal ArticleDOI
TL;DR: It is concluded that 72-hour in vivo treatment with 1,25-(OH)2 vitamin D3 increases contractile force-generating capacity of resistance arteries without affecting blood pressure.
Abstract: The hypothesis that 1,25-dihydroxyvitamin D3 [1,25-(OH)2 vitamin D3] modulates vascular smooth muscle contractile function was tested. 1,25-(OH)2 vitamin D3 (50 ng/day) was administered by intraperitoneal injection over a 3-day period to 13-15-week-old male spontaneously hypertensive and Wistar-Kyoto normotensive rats. On the fourth day, serum was prepared and contractile force generation of isolated mesenteric resistance arteries was examined. Treatment with 1,25-(OH)2 vitamin D3 approximately doubled serum levels of the hormone and increased ionized and total serum Ca2+ and phosphate by 5-10%. No effect on blood pressure was detected. 1,25-(OH)2 vitamin D3 injection in both strains enhanced maximal stress generation to norepinephrine and serotonin by 30-40%, with no effect on apparent sensitivity of the vessels to the agonists. To assess the effect of a maneuver that elevates serum ionized Ca2+ without the addition of exogenous hormone, maximal stress generation was examined in resistance arteries isolated from rats fed diets containing 0.5% or 2% calcium over a 6-7-week period. Maximal stress generation in response to norepinephrine was greater in vessels from rats of both strains maintained on 0.5% calcium. It is concluded that 72-hour in vivo treatment with 1,25-(OH)2 vitamin D3 increases contractile force-generating capacity of resistance arteries without affecting blood pressure. It is proposed that this action of 1,25-(OH)2 vitamin D3 is the result of a direct action of the hormone on the vascular wall.

Journal ArticleDOI
TL;DR: A comparison of the frequency of micronucleated PCE in peripheral blood and bone marrow following the treatment of mice with either BZD or DMBA suggests that, following a three injection protocol, either tissue can be used with equal efficacy.
Abstract: Studies were conducted to evaluate the effect of experimental protocol on the ability of benzidine (BZD), dimethylbenzanthracene (DMBA) and mitomycin C (MMC), administered by intraperitoneal injection, to induce micronuclei in polychromatic erythrocytes (PCE) of B6C3F1 mice. Three different treatment/sampling protocols were used, involving from one to three consecutive daily treatments and from three to one, respectively, consecutive daily samplings beginning 24 h after the last injection. DMBA and MMC elicited a significant micronucleus response in all three experimental protocols, while BZD induced a significant response only in the multiple injection protocols. Of the three protocols, the 3-day injection/single sample time protocol offers the greatest efficiency in minimizing the number of animals required in a study, in decreasing the time needed for scoring and in simplifying the statistical analysis. In addition, a comparison of the frequency of micronucleated PCE in peripheral blood and bone marrow following the treatment of mice with either BZD or DMBA suggests that, following a three injection protocol, either tissue can be used with equal efficacy.

Journal ArticleDOI
01 Jun 1990-Pain
TL;DR: In both species, bell‐shaped dose‐response curves were obtained, indicating that high doses of gentamicin had little or no effect, and the possible involvement of N‐type voltage‐sensitive channels in the mechanism of antinociception induced by gentamicine is considered.
Abstract: Intraperitoneal administration of gentamicin sulfate (5–800 μg/kg), but not gentamicin base (23–92 μg/kg) produced antinociception in rats and mice, as assessed by the tail-flick, carrageenan-induced articular incapacity tests, and hot-plate tests. The AD 50 s in rats (tail-flick test) and mice (hot-plate test) were 11.48 and 147.9 μg/kg, respectively, but doses of 200–800 μg/kg were required to reduce the hyperalgesia induced in rats by carrageenan. In both species, bell-shaped dose-response curves were obtained, indicating that high doses of gentamicin had little or no effect. Non-effective doses of gentamicin failed to produce a significant increase in morphine antinociception in either rodent species. The possible involvement of N-type voltage-sensitive. Ca 2+ channels in the mechanism of antinociception induced by gentamicin is considered.

Journal ArticleDOI
TL;DR: Measurements of MIBG lung extraction were able to demonstrate the presence of minimal endothelial cell lesions due to the BLM toxicity, and MibG is an index of pulmonary endothelial Cell function.
Abstract: Circulating biogenic amines, such as serotonin or norepinephrine, are cleared by the lung and can be considered as indicators of pulmonary endothelial integrity. An iodinated norepinephrine analogue, metaiodo-benzylguanidine (MIBG), is extracted in the lung by an active, saturable transport system. In order to investigate the use of MIBG lung extraction to detect minimal,lung endothelial cell lesions, an experimental model of initial pulmonary vascular lesions was developed in rats using repeated daily intraperitoneal injection of bleomycin (BLM: 2 U/100 g body weight) over a 5-day period. At this time, a significant decrease of serum angiotensin-converting enzyme activity, an index of endothelial cell metabolism, was observed (214±11 U/ml in controls as compared with 182±11 U/ml in BLM-treated rats,P < 0.05); electron microscopy showed the presence of typical but minimal endothelial cell lesions (blebbing). MIBG extraction (%EMIBG) was measured using the isolated perfused lung model after a 10-min steady-state period and 2 min of perfusion with123I-MIBG (0.1 μCi/ml) and125I-labelled human serum albumin (HSA) (0.2 μCi/ml). Intraperitoneal administration of BLM to rats for 5 days resulted in a significant decrease in pulmonary extraction of MIBG. %EMIBG declined from a control value of 24.7%±1.1% in controls to 19.3%±1.6% in BLM-treated rats (n=27,P<0.05; -21.2%). HSA lung extraction, used as an estimate of nonspecific residual lung activity, was not different in the lungs of BLM-treated rats as compared with controls. Because measurements of MIBG lung extraction (%EMIBG) were able to demonstrate the presence of minimal endothelial cell lesions due to the BLM toxicity, MIBG is an index of pulmonary endothelial cell function.

Journal ArticleDOI
TL;DR: It is demonstrated that the raised levels of arachidonic acid metabolites after pretreatment with GDM or AG seem to inhibit the otherwise lethal elevation of IL-1 and TNF in body fluids which is seen in untreated animals.
Abstract: The influences of pretreatment with beta-1,3-D-polyglucose derivatives on levels of cytokines and arachidonic acid metabolites in body fluids in experimental peritonitis in mice are reported. Peritonitis was induced by an intraperitoneal injection of 10(8) live Escherichia coli. Pretreated animals survived the infection, untreated animals died about 12 h after inoculation with E. coli. Levels of IL-1 in plasma and peritoneal fluid, measured by cytotoxicity assay of the HT-2 cell line, increased significantly during the first 48 h after intraperitoneal treatment with beta-1,3-D-polyglucose-derivatized microbeads (GDM) or soluble, aminated beta-1,3-D-polyglucose (AG). After subsequent challenge with E. coli, the levels of IL-1 were significantly lower than in untreated animals. There was no increase in levels of TNF after treatment with GDM or AG, measured by cytotoxicity assay of the WEHI clone 13 cell line. After challenge with E. coli, TNF in plasma and peritoneal fluid was significantly lower compared with untreated animals. Both PGE2 and LTB4, measured by radioimmunoassay kits, were increased in peritoneal fluid after treatment with GDM and AG. After challenge with E. coli, PGE2 and LTB4 in peritoneal fluid increased to about half the concentration of infected control animals. Intraperitoneal injection of indomethacin to pretreated animals resulted in increased levels of IL-1 and TNF and decreased levels of PGE2 following challenge with E. coli. The levels of IL-1 and TNF remained elevated until the animals died after about 12 h. These studies demonstrate that the raised levels of arachidonic acid metabolites after pretreatment with GDM or AG seem to inhibit the otherwise lethal elevation of IL-1 and TNF in body fluids which is seen in untreated animals.

Journal ArticleDOI
TL;DR: PKC activity is translocation from a cytosolic to a membrane‐bound form in the fetal brain and down‐regulation of PKC is accompanied by an increase in a Ca2+‐phosphatidylserinc‐indepcndent kinase [protein kinase M (PKM)] activity, suggesting that PKC down‐ regulation and PKM activity elevation are intimately associated events and that both are regulated by GM1 ganglioside.
Abstract: Complete obstruction of the maternal blood flow to fetal rats at 20 days of gestation for a period of 10 min causes a significant shift of approximately 22% in protein kinase C (PKC) activity from a cytosolic to a membrane-bound form in the fetal brain. This translocation can be entirely reversed without losses in activity by a single intraperitoneal injection into the gravid rat of either a mixture of disialo- and trisialoganglioside [polysialoganglioside (PSG)] or by GM1 (50 mg/kg of body weight) given 3 h before onset of the ischemic episode. Cessation of blood flow for 15 min followed by a reperfusion period of 24 h results in a 47% loss in total PKC activity. This down-regulation can be almost entirely prevented upon intraperitoneal administration of GM1 3 h before, but also during and even 90 min after the onset of ischemia. The PSG mixture is also effective, particularly when given 3 h before the insult. Down-regulation of PKC is accompanied by an increase in a Ca2(+)-phosphatidylserine-independent kinase [protein kinase M (PKM)] activity, which rises from 30 pmol/min/mg of protein in control animals to a maximal value of 83.1 pmol/min/mg of protein after 15 min of ischemia and 6 h of reperfusion. By 24 h, PKM activity is 46.8 pmol/min/mg of protein. Administration of GM1 blocks completely the appearance of PKM, a result suggesting that PKC down-regulation and PKM activity elevation are intimately associated events and that both are regulated by GM1 ganglioside.

Journal ArticleDOI
TL;DR: The liver tissue was most severely affected by the intraperitoneal injection of toxin, and hemorrhage, swelling and finally blood pooling in the tissue were observed.
Abstract: The lethal dosage of an extract of a toxic strain of Microcystis viridis or purified toxin, microcystin RR was determined against goldfish. The LD50 values of microcystin RR obtained by intraperitoneal injection into goldfish were just above 2 mg·kg-1 which was about 26 times higher than the known values for mice.Death of goldfish occurred rather slowly until 5th day, when the observation was terminated following injection of extract. The liver tissue was most severely affected by the intraperitoneal injection of toxin, and hemorrhage, swelling and finally blood pooling in the tissue were observed.Oral administration of Microcystis viridis as pellets mixed with the algae for 28 d did not cause any mortality but a few fish showed a slight liver damage.

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TL;DR: It is concluded that WEB 2086 ameliorated endotoxin-induced lung injury without reducing oxidative stress in the rat and suggested that blockade of platelet-activating factor receptor may be an important therapeutic consideration in sepsis-induced acute lung vascular injury.
Abstract: We tested the hypothesis that platelet-activating factor plays an important role in promoting endotoxin-induced lung injury by studying the effect of WEB 2086, a specific platelet-activating factor receptor antagonist, on lung vascular leak in endotoxin-treated rats. Intraperitoneal injection of Salmonella enteritidis endotoxin (2 mg/kg) increased the extravascular leakage of 125I-labeled albumin in perfused lungs at 30 min, 2 h, 6 h, and 48 h. Treatment with WEB 2086 (10 mg/kg ip) either 20 min before or 30 min after endotoxin injection significantly reduced lung injury at 2 h after endotoxin (leak index: control 0.74 +/- 0.03, endotoxin 1.79 +/- 0.14, endotoxin + pretreated WEB 1.23 +/- 0.09, endotoxin + posttreated WEB 1.21 +/- 0.13). In addition, posttreatment with WEB 2086 starting at 90 min after endotoxin injection markedly reduced lung leak at 6 h (control 0.74 +/- 0.03, endotoxin 1.29 +/- 0.14, endotoxin + WEB 0.71 +/- 0.06). The protective effect of WEB 2086 was not the result of cyclooxygenase blockade because the release of thromboxane B2 by endotoxin-treated lungs was not affected by WEB 2086. Furthermore, neither pretreatment nor posttreatment with WEB 2086 significantly reduced the endotoxin-induced increase in plasma glutathione disulfide, a marker of in vivo oxidative stress. In rats given a lethal dose of endotoxin (20 mg/kg ip), posttreatment with WEB 2086, starting at 2 h after endotoxin, significantly improved survival compared with vehicle treatment. We conclude that WEB 2086 ameliorated endotoxin-induced lung injury without reducing oxidative stress in the rat and suggest that blockade of platelet-activating factor receptor may be an important therapeutic consideration in sepsis-induced acute lung vascular injury.