Showing papers in "Experimental Biology and Medicine in 1978"
TL;DR: Results indicate that the carrier, albumin microspheres with entrapped Fe3O4, and adriamycin HCl, can be concentrated at a predetermined site in vivo by a magnetic field.
Abstract: SummaryA novel carrier system for the delivery of chemotherapeutic agents by magnetic means to desired sites has been developed. Results indicate that the carrier, albumin microspheres with entrapped Fe3O4, and adriamycin HCl, can be concentrated at a predetermined site in vivo by a magnetic field. Carrier delivery of adriamycin is supported by the presence of a significant concentration of the drug at the site of carrier localization. This delivery system allows for the accumulation of local adriamycin which is comparable to that achieved by administration of a 100-fold higher dose of the free drug.
415 citations
TL;DR: In studies of 3- to 5-month-old infants, there was some increase _in antibodies when a booster dose of vaccine was given 6 months after the first and very high level antibody responses were obtained when revaccination was delayed until 2 years of age.
Abstract: SummaryAdult persons developed substantial antibody increases against essentially all pneumococcal capsular types following injection of polyvalent pneumococcal vaccine containing 50 μg of each capsular polysaccharide per dose. Revaccination 13 months after the previous immunization did not evoke important further increases in antibodies and there was substantially greater local reaction at the injection site than when the previous dose was given. This finding appeared due to local reaction of antigens with circulating antibodies in the area of injection, since there was a correlation between the measured amount of circulating pneumococcal antibodies and the degree of reaction. Infants less than 2 years of age who were given a half-dose of vaccine generally responded poorly when compared with adults. In studies of 3- to 5-month-old infants, there was some increase _in antibodies when a booster dose of vaccine was given 6 months after the first. Very high level antibody responses against all capsular types...
244 citations
TL;DR: It is concluded that epidermal growth factor stimulated ornithine decarboxylase activity in the stomach and duodenum of neonatal mice suggesting a possible role for EGF (or urogastrone) in mucosal repair and defense in these tissues.
Abstract: SummaryThis study examined the effect of EGF (6 μg g-1 body wt, subcutaneously) on OD concentration in stomach, duodenum, midgut and colon, as well as a control tissue, heart, in 8-day-old mice. The animals were killed 4 hr after either EGF or control water injections. OD activity, expressed as picomoles of 14CO2 liberated from 1-[14C]l-ornithine per mg wet weight tissue, was significantly higher in the animals given EGF than in controls in the stomach (EGF 29.9 ± 6.8; control 9.9 ± 3.6, P < .05) and the duodenum (EGF 51.7 ± 16.9; control 6.5 ± 4.3, P < .05) but not in the midgut, colon or heart. It is concluded that epidermal growth factor stimulated ornithine decarboxylase activity in the stomach and duodenum of neonatal mice suggesting a possible role for EGF (or urogastrone) in mucosal repair and defense in these tissues.
137 citations
TL;DR: The observations support the contention that Peyer's patches “sample” intestinal contents and they suggest a mechanism for the elimination of accumulated inert particulate matter from these lymphoid structures.
Abstract: SummaryLatex particles (2 μm in diameter) accumulated in intestinal Peyer's patches and mesenteric lymph nodes of mice given latex suspensions as drinking fluid. After a 61-day period of latex feeding, the particles were also present in villi adjacent to Peyer's patches; they were not seen, however, after only 3 days of latex feeding. The amount of latex in Peyer's patches 74 days after the termination of latex feeding was much less than the amount present 14 days after the termination of feeding. It is suggested that migratory macrophages take up latex particles within Peyer's patches and subsequently move out of the patch to mesenteric nodes and villi. Some free particles may also be transported out of Peyer's patches to mesenteric nodes and villi through open lymphatic channels. The observations support the contention that Peyer's patches “sample” intestinal contents and they suggest a mechanism for the elimination of accumulated inert particulate matter from these lymphoid structures.
116 citations
TL;DR: Erythrocytes from zinc deficient rats, which had low plasma zinc and high plasma copper (low Zn:Cu), were more fragile than those from controls, and SOD activity is suggested as a clinical index of tissue copper status.
Abstract: SummaryErythrocytes from copper deficient rats, which had normal plasma zinc but low plasma copper (high Zn:Cu), were more stable to osmotic stress than those from controls. Erythrocytes from zinc deficient rats, which had low plasma zinc and high plasma copper (low Zn:Cu), were more fragile than those from controls. Addition of Cu2+ and Zn2+ to normal red cells in vitro to provide a low Zn:Cu ratio increased hemolysis and peroxidation. In general erythrocyte membranes are sensitive to the concentrations of extracellular Cu and Zn. The effects are inversely related, zinc exerting a stabilizing and copper a labilizing effect. Ceruloplasmin levels increased in zinc deficiency but RBC superoxide dismutase activity was unaffected. SOD activity is suggested as a clinical index of tissue copper status.
111 citations
TL;DR: The results support the conceptual framework integrating blood pressure regulation through the final common pathway of renal salt excretion and underscore the importance of salt regulation in the pathogenesis of hypertension.
Abstract: SummaryThe relationship between blood pressure and the state of salt balance was evaluated at four levels of salt intake (10 mEq/day, 300 mEq/day, 800 mEq/day, and 1500 mEq/day) in eight normal men. Increasing salt intake resulted in progressive increases in weight, blood pressure, potassium excretion, and creatinine clearance, while plasma renin activity and plasma aldosterone concentration decreased. Cardiac output increased with increasing salt intake, while calculated systemic vascular resistance decreased. The curve defining the relationship between salt excretion and blood pressure was derived. These results support the conceptual framework integrating blood pressure regulation through the final common pathway of renal salt excretion. Moreover, they underscore the importance of salt regulation in the pathogenesis of hypertension.
94 citations
TL;DR: The results confirm that the human parotid gland is highly sensitive to irradiation and suggest that virtually all of the oral fluid generated by the irradiated patient, even very early in the course of treatment, originates in glands other than theParotid.
Abstract: SummaryResting parotid flow rate response to irradiation was evaluated in seven patients. The mean for pretreatment flow was 0.045 ml/min (SD = 0.023). Twenty-four hours after the first treatment (225 rads) this mean had decreased to 0.023 ml/ min (SD = 0.022), and after the second treatment the mean was only 0.001 ml/min (SD = 0.002). Six of the seven patients exhibited no flow at all after 450 rads administered over 2 days, and the seventh flowed at a rate of only 0.005 ml/min. There was no detectable resting parotid flow from these patients after this time. These results confirm that the human parotid gland is highly sensitive to irradiation and suggest that virtually all of the oral fluid generated by the irradiated patient, even very early in the course of treatment, originates in glands other than the parotid.It is a pleasure to acknowledge the professional contribution of Dr. B. R. McCrary, and the technical assistance of Mr. Stephen L. Sorensen, Mr. Charles D. Steward, and Mrs. Bonnie B. Chance.
84 citations
TL;DR: Human hepatitis A virus, partially purified from the liver of a rufiventer marmoset infected with CR326 strain virus, was inactivated with formalin and was shown to be highly potent in stimulating homologous antibody in marmosets when administered subcutaneously at bi-weekly intervals in eight divided doses.
Abstract: SummaryHuman hepatitis A virus, partially purified from the liver of a rufiventer marmoset infected with CR326 strain virus, was inactivated with formalin and was shown to be highly potent in stimulating homologous antibody in marmosets when administered subcutaneously at bi-weekly intervals in eight divided doses The vaccine was shown to prevent hepatitis A in all marmosets when challenged with live hepatitis A virus in a controlled study
82 citations
TL;DR: The meningococcal polysaccharide vaccine was found to be clinically acceptable and a significant antibody response was detected by both a bactericidal assay and a solid-phase radioimmune assay.
Abstract: SummaryThe clinical and serological testing of a groups A, C, and Y meningococcal polysaccharide vaccine is described. Some minor reactions were observed. High levels of bactericidal antibody to all three components were observed in 90% of the individuals 3 weeks after receiving the vaccine.
72 citations
TL;DR: Bran in the diet had little effect on the incidence, number, and distribution of duodenal tumors and intestinal transit times were decreased and fecal outputs were increased in rats given the 20% bran diet.
Abstract: SummaryThe putative role of dietary fiber was investigated in dimethylhydrazine (DMH)-induced colon carcinogenesis in rats. Four groups of 10 male Sprague-Dawley rats each were used: Group I-Control; Group 11-30 mg/kg DMH; Group III-20% bran; and Group IV-Bran and DMH. Intestinal transit times were decreased and fecal outputs were increased in rats given the 20% bran diet. In Group 11, all 10 rats had tumors with a mean of 6.4 tumors/rat whereas in Group IV, 6 of 9 rats (67%) had tumors with a mean of only 1.8 tumors/rat/group and 2.7 tumors/rat which had tumors. The size and distribution of these tumors were similar in both groups. Bran in the diet had little effect on the incidence, number, and distribution of duodenal tumors.
68 citations
TL;DR: The findings fail to support the conclusion that antisera to rough gram-negative bacterial mutants confer broad spectrum protection to mice against parenteral challenge with smooth Enterobacteriaceae because of the rise in antibody titer to common core antigens.
Abstract: SummaryRabbit antisera to three rough Enterobacteriaceae mutants, the Rc chemotype of Escherichia coli J5, the Rd chemotype of Salmonella typhimurium SL 1032, and the Re chemotype of Salmonella minnesota 595, were administered iv or ip to outbred Swiss albino mice. Control animals were injected concomitantly with normal serum from the same donors obtained prior to immunization. One hour later, challenge was performed ip or iv with LD95-100 doses of viable Escherichia coli 018, Proteus mirabilis, or Klebsiella pneumoniae. Normal pre-immune rabbit sera, lacking detectable antibodies to the specific challenge bacterial strains or to Ra, Rc, Rd, or Re rough mutants of Enterobacteriaceae, exhibited definite abilities to reduce septic mortality when compared with physiologic sterile saline. Analysis of preimmune sera from individual rabbit donors revealed a wide spectrum of protective activity. Post-immune sera against the rough bacterial mutants, possessing high titers of Rc, Rd, or Re antibodies, conferred no...
TL;DR: Granulocyte fractions, containing an average of about 92% neutrophils, were isolated from bovine blood and the electron microscope observation of these fractions showed that neutrophil granules have different shapes, but are all highly and homogeneously electron-dense.
Abstract: SummaryGranulocyte fractions, containing an average of about 92% neutrophils, were isolated from bovine blood. The electron microscope observation of these fractions showed that neutrophil granules have different shapes, but are all highly and homogeneously electron-dense. With respect to the granulocytes of human blood, bovine cells appear to have a lower content of azurophil enzymes and virtually lack lysozyme. Lysates of bovine granulocytes efficiently kill both E. coli (at pH 6.0 and 7.4) and S. aureus (mainly at pH 7.4). When exposed to opsonized B. mycoides, intact bovine granulocytes exhibit a marked enhancement in oxygen consumption, generation of O2- and H2O2, and glucose oxidation through the hexose monophosphate pathway. About 15% of the total oxygen reduced is recovered extracellularly as O2-. Hydrogen peroxide generated by phagocytizing cells is only partially utilized in reactions catalyzed by catalase and myeloperoxidase, and appears to mainly enter the glutathione cycle.
TL;DR: The hypothesis that the teratogenic effects of zinc deficiency are associated with the enzymes involved in DNA synthesis is supported by the findings of this research.
Abstract: SummaryThymidine kinase and DNA polymerase activities were significantly (P < 0.05 and P < 0.01, respectively) lower in 9, 10, 11, and 12-day embryos taken from dams fed a zinc deficient diet than in those from ad libitum fed and restricted intake controls. An additional finding was that of increased activity of both thymidine kinase and DNA polymerase with increasing age of embryos. As previously found with thymidine kinase, addition of zinc and other divalent metal ions in vitro had little effect on restoration of DNA polymerase activity from zinc deficient extracts when added at concentrations of 0.01 and 0.05 mM. When added at a level of 0.2 mM, zinc, but not other metal ions, had an inhibitory effect on DNA polymerase activity. These findings support the hypothesis that the teratogenic effects of zinc deficiency are associated with the enzymes involved in DNA synthesis.This research was supported in part by NIH Research Grant No. HD-01743 from the National Institute of Child Health and Human Development.
TL;DR: The possibility that some contaminants present in the immune interferon preparation could nonspecifically interfere with the rapid induction phenomenon is not supported by the finding that the rapid kinetics of cell activation by virus-induced interferons was not modified by the presence of immuneinterferon.
Abstract: Summary The kinetics of activation of the antiviral state by virus induced interferon and by mitogen-induced immune interferon have been studied comparatively. It has been found that both human and murine virus-induced interferons are able to activate the antiviral state after a brief (minutes) contact with the cells. In contrast, several hours were required for both human and mouse immune interferons to induce a comparable level of antiviral resistance. Experiments measuring the binding of the two interferons to cells showed that there was no significant difference in the rate and degree of binding, suggesting that a different total association of interferon with cells could not account for the slower kinetics of activation by immune interferon. Additionally, the possibility that some contaminants present in the immune interferon preparation could nonspecifically interfere with the rapid induction phenomenon is not supported by the finding that the rapid kinetics of cell activation by virus-induced interferon was not modified by the presence of immune interferon. The interesting possibility which remains is that the two interferons may activate cells by different mechanisms. The authors are greatly indebted to Dr. G. Georgiades and Mr. M. Langford for the generous gifts of immune interferon and to Dr. S. Baron for helpful suggestions and criticism.
TL;DR: Pulmonary catalase activity, however, was lower in the older rats compared to the younger animals, and from day 12 to 70, these enzymes and reduced glutathione generally showed a gradual increase in activity levels with age.
Abstract: SummaryThe age-related development of the activity levels of the pulmonary an-tioxidant defense systems: superoxide dismutase, reduced glutathione, glutathione peroxidase, glutathione reductase and catalase, were examined in the rat. All the pulmonary antioxidant enzymes studied showed a lower activity at two days before term than at birth. From day 12 to 70, with the exception of catalase, these enzymes and reduced glutathione generally showed a gradual increase in activity levels with age. Pulmonary catalase activity, however, was lower in the older rats compared to the younger animals. No significant differences were found in the various pulmonary enzyme activities and glutathione levels between male and female rats.
TL;DR: Calculations of body iron turnover have been made and a general inverse relationship between body size and rate of external iron exchange is established and a comparison of iron requirements and iron intake in these animals indicate extremely low absorption requirements.
Abstract: SummaryMeasurements have been made of the decrease in specific activity of radioiron in circulating red cells of eight animal species. From these data calculations of body iron turnover have been made and establish a general inverse relationship between body size and rate of external iron exchange. A comparison of iron requirements and iron intake in these animals indicate extremely low absorption requirements, ranging from 0.2 to 2.3% of their dietary iron intake.
TL;DR: Two synthetic morphine analogs, butorphanol and oxilorphan have been found to inhibit suckling induced oxytocin (OT) release in lactating mice, and the analgesic property of these compounds is responsible for the inhibition.
Abstract: SummaryTwo synthetic morphine analogs, butorphanol and oxilorphan have been found to inhibit suckling induced oxytocin (OT) release in lactating mice. Morphine when tested in a similar experimental set-up produced even greater inhibition. Naloxone could effectively block inhibitions induced both by butorphanol and by morphine. When injected alone, naloxone did not produce any inhibition. These results indicate that (a) butorphanol, oxilorphan and morphine inhibit suckling induced OT release in mice, (b) the analgesic property of these compounds is responsible for the inhibition, and (c) inhibition produced by morphine and butorphanol is specific in nature since it could be reversed by naloxone.
TL;DR: Conversion of AI to AII and inactivation of bradykinin are regulated by converting enzyme and the decrease in AI conversion during acute alveolar hypoxia could be related to hemodynamic factors in the pulmonary vasculature induced by Hypoxia.
Abstract: SummaryConversion of AI to AII and inactivation of bradykinin are regulated by converting enzyme. In this study, conversion of AI in vivo is decreased during acute alveolar hypoxia. At a PaO2 of 30 mm Hg, conversion of AI is decreased to one half control values. The decrease in AI conversion could not be related to hemodynamic factors in the pulmonary vasculature induced by hypoxia. It may be related to the effects of hypoxia on endothelial cell function or conformation.
TL;DR: Nonpregnant, pregnant and progesterone treated mice were infected intravaginally with HSV II and the increased susceptibility of pregnant mice was simulated by administration of progester one to nonpreg pregnant female mice.
Abstract: SummaryNonpregnant, pregnant and progesterone treated mice were infected intravaginally with HSV II. Mortality rates were 10%, 88% and 88% respectively. Progesterone levels were 80–100 times greater in the treated mice and 10–70 times greater in the pregnant mice than controls. We were able to simulate the increased susceptibility of pregnant mice by administration of progesterone to nonpregnant female mice.
TL;DR: Study of bovine aortic actomyosin employing isoelectric focusing and sodium dodecyl sulfate electrophoresis suggest that the Ca2+ regulatory mechanism for actin-myosin interactions in mammalian vascular smooth muscle may be partly mediated by phosphorylation of myosin light chains.
Abstract: SummaryStudies of bovine aortic actomyosin employing isoelectric focusing and sodium dodecyl sulfate electrophoresis show Ca2+ dependent phosphorylation of 15,000 dalton polypeptides. These polypeptides probably correspond to the myosin light chains. The Ca2+ requirement for phosphorylation parallels the Ca2+ requirement for activation of Mg2+ stimulated actomyosin ATPase. These findings suggest that the Ca2+ regulatory mechanism for actin-myosin interactions in mammalian vascular smooth muscle may be partly mediated by phosphorylation of myosin light chains.
TL;DR: The present data indicate that zinc can be released from bone during periods of dietary zinc deficiency, and the decrease in zinc appears to be independent from calcium and phosphorus in the bone.
Abstract: SummaryAlterations in bone mineralization were examined during the progression of a zinc deficiency in rats. One hundred rats were divided into three groups and fed the following diets: zinc sufficient, ad libitum; zinc deficient, ad libitum; and zinc sufficient, pair-fed the daily intake of the deficient group. Plasma zinc concentration of the zinc-deficient group decreased dramatically during the first 24 hr of deficient diet and continued to decline over the next 2 days. Body weight gain essentially stopped after 1 week. During the experimental period of 23 days, femur zinc concentration decreased 61%, while total femur zinc decreased 37%. Yet, both the total and concentration of calcium and phosphorus increased and the Ca:P ratio remained relatively constant. The present data indicate that zinc can be released from bone during periods of dietary zinc deficiency. Furthermore, the decrease in zinc appears to be independent from calcium and phosphorus in the bone.
TL;DR: Rat and mouse PMNs had negligible catalase activities and enhanced HMP shunt activity reflecting their relative dependence on the more active GPX and GR enzyme systems compared to human and guinea pig PMN which depend more heavily on the cytoplasmicCatalase for disposal of peroxide.
Abstract: SummaryCatalase and the glutathione system containing GPX and GR offer the PMN two mechanisms for disposal of peroxide during phagocytosis. Catalase requires peroxide as substrate whereas GPX requires peroxide and reduced glutathione which is regenerated by GR and NADPH from the HMP shunt. Impairment of either system may lead to accumulation of toxic amounts of peroxide potentially affecting phagocytic function. The activities of catalase compared to GPX and GR were reciprocally related in four mammalian species. Rat and mouse PMNs had negligible catalase activities and enhanced HMP shunt activity reflecting their relative dependence on the more active GPX and GR enzyme systems compared to human and guinea pig PMN which depend more heavily on the cytoplasmic catalase for disposal of peroxide.
TL;DR: It is proposed that the hypotension and renal vasodilation seen after SQ 14,225 could be due to loss of endogenous AII; however, an enhancement of endogenously produced bradykinin cannot be excluded.
Abstract: SummaryThe hemodynamic and renal vascular effects of SQ 14,225, a new angiotensin-converting enzyme inhibitor, were studied in mongrel dogs under pentobarbital anesthesia. A dose-related inhibition of the pressor and renal vasoconstrictor effects of AI, but not of AII, were seen after SQ 14,225. After administration of SQ 14,225 (310 μg/kg iv) a moderate decrease in arterial pressure and increase in renal blood flow were observed. It is proposed that the hypotension and renal vasodilation seen after SQ 14,225 could be due to loss of endogenous AII; however, an enhancement of endogenously produced bradykinin cannot be excluded.
TL;DR: Serotonin turnover, as measured by the rate of 5-hydroxyindoleacetic acid accumulation after probenecid administration, was decreased significantly still at 1 week after fenfluramine administration.
Abstract: SummaryFenfluramine and its N-demethyl metabolite, norfenfluramine (3-tri-fluoromethyl-amphetamine), lowered brain serotonin, 5-hydroxyindoleacetic acid, and tryptophan hydroxylase in rats acutely and the effect persisted for more than 1 week after a single ip dose of the drugs. Serotonin depletion by fenfluramine and norfenfluramine was blocked by pretreatment with fluoxetine, an inhibitor of uptake into serotonin neurons. Serotonin turnover, as measured by the rate of 5-hydroxyindoleacetic acid accumulation after probenecid administration, was decreased significantly still at 1 week after fenfluramine administration. The effects of fenfluramine and norfenfluramine on brain serotonin neurons in rats resemble those of p-chloroamphetamine and probably occur via similar mechanisms.
TL;DR: In this article, the oxygen consumption of obese mice was determined daily from birth to 19 days of age and weekly thereafter until 16 weeks of age in lean and obese mice, and the results showed that alterations in energy metabolism occur very early in the life of obesity mice.
Abstract: SummaryRates of oxygen consumption were determined daily from birth to 19 days of age and weekly thereafter until 16 weeks of age in lean and obese mice. As early as 5 days after birth obese mice consumed less oxygen than lean mice. Obese mice weighed more than lean mice by 6 days of age and contained 38% more fat than lean mice at 7 days of age. At 14 days of age obese mice contained 53% more fat than lean mice. Beyond 3 weeks of age oxygen consumption of obese mice was less than observed in lean mice when the results were expressed per g body weight, but the values for obese and lean mice were similar when expressed per animal. These results demonstrate that alterations in energy metabolism occur very early in the life of obese mice.
TL;DR: A spectrophotometric assay has been developed in which sodium perborate, rather than hydrogen peroxide, is used as the substrate, which is convenient, rapid, and readily adapted to the measurement of catalase in subcellular fractions.
Abstract: SummaryA spectrophotometric assay for catalase has been developed in which sodium perborate, rather than hydrogen peroxide, is used as the substrate. The method is convenient, rapid, and readily adapted to the measurement of catalase in subcellular fractions.
TL;DR: The results suggest that antinatriferic factor is a small acidic peptide, formed from a precursor molecule that was isolated from VE dog plasma on high pressure liquid chromatography.
Abstract: SummaryAntinatriferic factor was isolated from VE dog plasma on high pressure liquid chromatography. The use of an enzyme inhibitor while collecting plasma reduced the presence of this factor. A reverse-phase chromatography peptide map revealed 2 peptides whose presence was directly correlated with antinatriferic activity. The results suggest that antinatriferic factor is a small acidic peptide, formed from a precursor molecule. Reverse-phase chromatography may prove to be a chemical assay for antinatriferic factor.
TL;DR: It is suggested that hypokalemia, by stimulation of the synthesis of prostaglandin E in the kidney, produces hyperreninemia, which increases the vascular resistance to angiotensin II and to norepinephrine.
Abstract: SummaryThe role of hypokalemia and increased synthesis of prostaglandins in the decreased response of blood pressure to intravenous angiotensin II was studied in patients with Bartter's syndrome and in patients with psychogenic vomiting. In patients with Bartter's syndrome with high urinary prostaglandin E, treatment with an inhibitor of prostaglandin synthesis corrected the hyperreninemia and restored the pressor response to angiotensin II to normal but only partially corrected the hypokalemia. In patients with psychogenic vomiting with high urinary prostaglandin E, correction of the hypokalemia corrected the hyperreninemia and restored the pressor response to angiotensin II and to norepinephrine to normal. The findings suggest that hypokalemia, by stimulation of the synthesis of prostaglandin E in the kidney, produces hyperreninemia. An increase in synthesis of prostaglandin E in vascular tissue, stimulated by hypokalemia per se or by angiotensin II (produced by the hyperreninemia) or by both, increases...
TL;DR: Heart perfused with 95% N2-5% CO2 demonstrated a significant decrease in tissue taurine content when compared to control hearts perfused to demonstrate cellular hypoxia, and metabolic conversion of tauri had no role in the disappearance of t aurine from the rat heart.
Abstract: SummaryThe effects of cellular hypoxia on taurine levels in rat hearts were determined. Hearts perfused with 95% N2-5% CO2 demonstrated a significant decrease in tissue taurine content when compared to control hearts perfused with 95% O2-5% CO2. The loss of taurine in oxygen-deficient hearts was time dependent over a period of 30 min. The perfusate when analyzed for taurine content contained 100% of the released taurine. Thus, metabolic conversion of taurine had no role in the disappearance of taurine from the rat heart.
TL;DR: Stimulated human monocytes produce two physically distinct pyrogens that will lower plasma iron and zinc and increase blood neutrophils when injected into rats or rabbits, providing evidence that leukocytic endogenous mediator can be produced by monocytes as well as by granulocytes.
Abstract: SummaryStimulated human monocytes produce two physically distinct pyrogens. Both of these partially purified pyrogens will lower plasma iron and zinc and increase blood neutrophils when injected into rats or rabbits. When equivalent pyrogenic doses were injected, the two pyrogens gave quantitatively similar leukocytic endogenous mediator activities (i.e., granulocytosis and lowering of plasma iron and zinc). These results, therefore, provide evidence that leukocytic endogenous mediator can be produced by monocytes as well as by granulocytes.