Showing papers in "Indian Journal of Experimental Biology in 1989"

Effect of carnitine on malondialdehyde, taurine and glutathione levels in heart of rats subjected to myocardial stress by isoproterenol.

Abstract: The effect of carnitine on free fatty acid, malondialdehyde, taurine and glutathione levels in myocardium was studied in rats administered isoproterenol to induce a stress in the myocardium resulting in myocardial ischaemia. Carnitine decreased the levels of free fatty acid and malondialdehyde (an index of lipid peroxidation) when compared to control rats given isoproterenol alone. Taurine and glutathione also registered a fall in the carnitine treated animals when compared to rats treated with isoproterenol alone. The results indicate that carnitine by decreasing the levels of these parameters helps the myocardium to survive from the stress induced by isoproterenol.

Toxic effects of garlic extract and garlic oil in rats

Abstract: Significant rise in urea and D-aspartate aminotransferase and inhibition of alkaline phosphatase in serum were observed in rats fed garlic extract (2 ml/100 g body wt, intragastrically) for 10 days. The liver showed histological changes. Garlic oil feeding (10 mg/100 g body wt, intragastrically) after 24 hr fasting was found lethal. The cause of death appears to be acute pulmonary oedema. On histological examination, all the organs of the dead rats revealed severe congestion. However, similar feeding of garlic oil was well tolerated by rats in the fed state. Also, 24 hr fasted rats could tolerate this dose of garlic oil, provided they were previously adapted to garlic oil feeding.

Induction of lipid peroxidation in calcium oxalate stone formation.

Abstract: The function of lipid peroxidation and the anti-peroxidative enzymes of rat liver and kidney were investigated under hyperoxaluric and stone forming conditions. The experimental animals showed higher malondialdehyde content in liver and kidney than that of control. A significant increase in malondialdehyde release was observed in the experimental liver or kidney when incubated with either ferrous sulphate or hydrogen peroxide compared to that of control liver or kidney. Superoxide dismutase activity was not affected in the hyperoxaluric rats while there was a moderate increase in the stone forming rats when compared to control. Highly significant decrease in catalase activity was observed in both conditions in liver and kidney compared to control.

Reversal of changes of lipid peroxide, xanthine oxidase and superoxide dismutase by cardio-protective drugs in isoproterenol induced myocardial necrosis in rats.

Abstract: In myocardial necrosis produced by isoproterenol (beta-adrenergic agonist) marked increase in creatine phosphokinase, phospholipase and significant decrease in cardiac glycogen and phospholipid levels were observed. The enhanced levels of lipid peroxides, xanthine oxidase activity and lowering of superoxide dismutase may lead to excessive formation of free radicals resulting in cardiac cell damage. Nifedipine--a calcium antagonist, Propranolol--a beta-blocker and guggulsterone a lipid lowering agent showed marked reversal of these metabolic changes related to ischemia induced by isoproterenol.

Toxicity of endosulfan on kidney of male rats in relation to drug metabolizing enzymes and microsomal lipid peroxidation.

Abstract: Endosulfan administration (po, 15 and 30 days at 7.5 and 10 mg/kg body wt respectively) inhibited the activity of microsomal mixed function oxidases in kidney tissue of male rats. Microsomal and cytosolic protein contents of kidney were significantly increased following 30 days endosulfan exposures. Profound induction in the activity profiles of alcohol dehydrogenase and cytosolic glutathione s-transferase was noticed, however, no such change was apparent in the activity of aldehyde dehydrogenase. Microsomal preparations from treated animals showed a dose and duration dependent increase in spontaneous lipid peroxidation. The observed biochemical changes persisted even after 7 days normalcy allowance provided after the endosulfan (10 mg/kg body wt) withdrawl. The results suggest a substantial renal toxicity of endosulfan to male rats in relation to microsomal mixed function oxidases and associated functions which possibly resulted from lipid peroxidative damage of microsomal membrane in treated animals.

Antifertility effect of Piper betle Linn. extract on ovary and testis of albino rats.

Abstract: Chronic administration (sc) of the extract of the stalk of P. betle at 30 mg/kg body weight daily for 21 days produced significant decrease in oestrogen and androgen dependent target organ weights along with increase in cholesterol in adrenal, ovary and testis. Acid and alkaline phosphatase activities in serum, liver and kidney did not exhibit any toxic effect. There was marked change in morphology of testis and ovary. Vaginal smear showed prolonged dioestrus in treated female. The treated male showed decreased number and motility of sperm. Both male and female remained infertile after treatment suggesting antifertility activity of the extract on both sexes of albino rats.

Influence of industrial pollutants on thyroid function in Channa punctatus (Bloch).

Abstract: A 30 day exposure of C. punctatus to sublethal levels of phenol, ammonia, mercuric chloride, cadmium chloride and a mixture of the four resulted in an overall activation of guaiacol peroxidase and depression of iodide peroxidase (IPOD) activity and blood T4 titre. Interestingly enough, in case of 15 day ammonia and 1 day mercury exposures, an increase of IPOD activity was accompanied by a decrease in T4 titre. In general, phenol, mercury, cadmium and the mixture of pollutants were found to inhibit LP activity by 56% to 85% while ammonia inhibited lysosomal protease (LP) activity by 70%. Alterations in acid phosphatase (AP) activity indicate changes in the lysosomal membrane characteristics caused by these toxicants. Considering the concomitant alterations in IPOD, T4, LP and AP it is surmised that thyroid function in C. punctatus is influenced by the pollutants by two pathways, one via IPOD pathway affecting T4 synthesis and the other via lysosomal pathway affecting T4 release.

Adaptogenic activity of Indian Panax pseudoginseng.

Abstract: The crude extract and saponins of Indian pseudoginseng and saponins of Korean ginseng have been studied using a battery of biological tests in rats and mice. Indian pseudoginseng saponins were found to exhibit better activity than the Korean ginseng saponins in several tests employed. The results indicate a need for in-depth study of Indian pseudoginseng as an adaptogenic agent, after cultivation of the plant under controlled conditions.

Effect of b (beta)-adrenoceptor antagonists and some related drugs on maximal electroshock seizures in mice

Abstract: (+/-) Propranolol (1-50 mg/kg), (+) propranolol (50 mg/kg) and pindolol (10-50 mg/kg) exhibited significant protective effects against MES (maximum electroshock seizures), whereas, timolol (1 mg/kg), the propranolol analog, UM-272 (1 and 10 mg/kg), and the beta-agonist, terbutaline (1 and 10 mg/kg) were ineffective. Cholinergic agents, physostigmine (0.01-1.0 mg/kg), and atropine (1 and 10 mg/kg), the serotonin antagonist, cyproheptadine (0.05 mg/kg), and the prostaglandin synthesis inhibitor, indomethacin (10 mg/kg), were also without effect on the MES extensor phase. Further, pretreatment of mice with terbutaline, atropine, cyproheptadine or indomethacin did not influence the anti-MES effect of propranolol to any significant extent. The results indicate that the observed anticonvulsant effects of beta-adrenoceptor antagonists are unrelated to noradrenergic or other central neurotransmitter systems and that a non-specific mechanism, probably a membrane stabilizing effect is involved.

In vivo distribution of lithium in plasma and brain.

Abstract: A single administration of LiCl (0.5, 2 and 4 mmol/kg) to adult male albino rats produced a dose dependent increase of Li level in plasma, whole brain and brain regions. The concentration of Li in whole brain and brain regions was much less than that in plasma. Further, it is also found that concentration of Li in plasma reached a peak at 8 hr while that of Li in whole brain and brain regions reached a peak at 12 hr after the administration. The distribution and retention of Li was found to be highest in hypothalamus followed by striatum, pons-medulla, cerebellum and cerebral cortex. Daily administration of LiCl at a dose of 0.5 and 2 mmol/kg/day showed a time and dose dependent increase in plasma Li level up to a period of 21 consecutive days. But at higher dose (4 mmol/kg/day), on the other hand, under similar condition showed a time dependent increase in plasma Li level up to a period of 14 consecutive days and then gradually decreased with prolongation of treatment to 21 consecutive days. In brain there was no such decrease, rather increase in Li level was observed with the prolongation of duration of treatment, highest concentration of Li was found in hypothalamus and striatum than the rest of the brain regions. These results suggest that under short term treatment with LiCl, the clearance rate of Li in brain cell is much slower than that in plasma. Both single and long-term exposure of LiCl produces a dose dependent increase of Li in plasma, whole brain and brain regions.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of capsaicin on skeletal muscle lipoprotein lipase in rats fed high fat diet.

Abstract: A synthetic analogue of capsaicin (0.2 mg%) fed to female Wistar rats along with a high fat diet for 11 weeks, lowered adipose tissue weight and also liver and serum triglycerides. The compound elevated total post heparin plasma lipase and skeletal muscle lipase activities. The increase in the latter indicates the possible mechanism by which capsaicin enhances serum triglyceride uptake by muscle tissue and in turn lowers triglyceride levels. A single dose of capsaicin even at a much higher level failed to lower serum triglycerides emphasizing the necessity of continuous ingestion of capsaicin for exerting its hypolipidemic effect.

Hydrocarbon emulsification by Candida tropicalis and Debaryomyces polymorphus.

Abstract: Potentiality of C. tropicalis and D. polymorphus, to produce surface active compounds (bioemulsifiers/biosurfactants) during shake cultivation on hexadecane and oily waste was studied. Better emulsification activity, specific towards aromatic hydrocarbons, was observed with C. tropicalis culture broth. Emulsification activity of culture broth was quite stable and was unaffected by change in pH and by increasing the concentration of NaCl up to 5%. The activity was marginally affected by heating in boiling water bath for 15 min, but inhibited to the tune of 90% by 0.3% CaCl2. The isolated bioemulsifying factor contained 40, 22 and 17.5% lipid, protein and carbohydrate, respectively.

Gonadal toxicity of short term chronic endosulfan exposure to male rats.

Abstract: Endosulfan was studied for its effect on rat testicular toxicity in relation to the enzymes of androgen biosynthesis, viz. 3 beta-hydroxysteroid dehydrogenase (EC 1.1.1.145, 3 beta-HSD) and 17 beta-hydroxysteroid dehydrogenase (EC 1.1.1.64, 17 beta-HSD); cytosolic conjugation enzyme, glutathione-S-transferase (EC 2.5.1.18); and testicular as well as serum testosterone levels at the dose levels of 2.5, 5.0, 7.5 and 10 mg/kg body weight fed orally for 7 and 15 days. Organ and body weights of the treated animals did not change significantly, however, the testicular protein contents were found to be increased appreciably after 7 days treatments. The activity profile of cytosolic conjugation enzyme showed much remained low during 7 days treatment, however, the two steroidogenic enzymes showed much individual variations in response to endosulfan treatments. An overall varied response with respect to testosterone biosynthesis and its secretion to serum was observed suggesting nevertheless, a profound hormonal imbalance caused by this insecticide to male gonads on short term chronic exposures.

Pharmacology of Acorus calamus L.

Abstract: Water soluble dried powder of alcoholic extract of roots and rhizomes of A. calamus L. was used. The in vivo experiments involved strychnine convulsant activity in frogs, spontaneous motor activity and amphetamine hyperactivity in mice, pentobarbitone sleeping-time in rats and local anaesthetic activity in guinea pigs and rabbits. Frog skeletal muscle and heart preparations and rat phrenic nerve diaphragm constituted the in vitro experiments. Plant extracts at 10, 20 mg/kg ip did not afford protection to strychnine (1,5,2.5 mg/kg) induced convulsions and same effect was found on acetylcholine induced contractions of rectus muscle except that it inhibited caffeine citrate contractions in frog. At 1, 10 and 100 micrograms/ml doses, it caused negative iono- and chronotropic effects in frogs. Dosages of 10, 25, 50 mg/kg ip of herbal extract antagonize spontaneous motor activity and also amphetamine induced hyperactivity in mice. It was less potent than chloropromazine, though exerts sedative and tranquilizing action. Local anaesthetic activity was found to be absent at 0.5 and 1% dose levels.

A cytotoxic substance produced by a wild culture of Lactobacillus casei D-34 against tumour cells.

Abstract: A wild lactic culture isolated from dahi (fermented milk) sample and characterised as L. casei D-34 was found to be significantly cytotoxic (34-36%) against three tumour cell lines, HeLa, HEp-2 and HFS-9. The cytotoxic substance (CS) was found to be in the culture supernatants, protein in nature, with a molecular weight ranging from 17,000-20,000. The crude culture supernatant was partially purified by dialysis and ion exchange chromatography as anionic, cationic and neutral fractions. Among the fractions, except for the anionic fraction, others were found to be highly cytotoxic against all three tumour cell lines. The cationic, neutral and pooled (anionic:cationic:neutral in 1:1:1 ratio) fractions showed 50, 70, 70% cytotoxicity against Hep-2 cells, 70, 88, 94% against HFS-9 cells and 50, 89, 90% against HeLa cells respectively. Pooled fraction was found to exhibit higher percent of cytotoxicity compared to individual fractions indicating a synergistic effect. (3H)-thymidine incorporation studies revealed that CS and its fractions inhibited DNA synthesis in tumour cells. The CS was stable towards heat and pH changes.

Effect of Emblica officinalis Gaertn. (Indian gooseberry) fruit extract on sodium azide and 4-nitro-o-phenylenediamine induced mutagenesis in Salmonella typhimurium.

Abstract: Water, acetone and chloroform extracts of E. officinalis fruit reduced sodium azide and NPD induced his+ revertants significantly in TA100 and TA97 a strains respectively of S. typhimurium. The chloroform extract was less active as compared to water and acetone extracts. Autoclaving of water extract for 15 min did not reduce its activity. The enhanced inhibitory activity of the extracts on pre-incubation suggests the possibility of desmutagens in the extracts. Besides ascorbic acid, a constituent of the extract, the role of other antimutagenic factors in the extract cannot be ruled out.

Acute pancreatitis and reduction of H+ ion concentration in gastric secretions in experimental acute myocarditis produced by Indian red scorpion, Buthus tamulus, venom.

Abstract: Crude venom (4 mg/kg) of scorpion (B. tamulus) was given in saline to anaesthetized dogs and rabbits. It produced a reduction in gastric H+ ion concentration in dogs with acute myocarditis. Simultaneously an increase in circulating amylase and lipase level was also observed. However 60% venom poisoned rabbits showed an elevated lipase level without a parallel increase in amylase. It is suggested that the venom acts directly on exocrine pancreas to cause acute pancreatitis.

Effect of piracetam, a nootropic agent, on rat brain monoamines and prostaglandins.

Abstract: Piracetam is the prototype of a new class of psychotropic drugs, the nootropic agents, which are claimed to selectively improve the higher telencephalic integrative activities The effect of piracetam on rat brain monoamines and prostaglandins (PGs) was assessed so as to garner information on its mode of action Two doses of the drug were used, a lower dose (20 mg/kg ip) and a higher dose (100 mg/kg, ip), the latter being known to exert a facilitatory effect on learning and memory Piracetam produced a dose-related effect on rat brain serotonin (5HT) and noradrenaline (NA), with the lower dose inducing a decrease in 5HT levels and an increase in NA concentrations The higher dose of piracetam produced the opposite effect Dopamine (DA) levels were not significantly affected The lower dose of the drug attenuated 5HT turnover and augmented that of NA, whereas the higher dose of piracetam produced the reverse effects, in clorgyline treated rats The lower dose of piracetam produced a slight and statistically insignificant increase in rat brain PGE2 and PGF2 alpha However, the higher dose of the drug produced marked increase in the levels of both the PGs The observed biochemical effects may provide a basis for the nootropic effect of piracetam However, they may also be due to the GA-BA-mimetic action of the drug, particularly those observed with the lower dose of piracetam

Effect of ayurvedic medicines on beta-glucuronidase activity of Brunner's glands during recovery from cysteamine induced duodenal ulcers in rats.

Abstract: Biochemical and histochemical studies revealed decreased beta-glucuronidase activity in the Brunner's glands of duodenal ulcerated rats. The enzyme activity showed gradual increase during recovery. Rats treated with a mixture of Ayurvedic medicines (Glycyrrhiza glabra, Terminalia chebula, Piper longum and Shanka Bhasma) recovered faster with concomitant increase in beta-glucuronidase activity in the Brunner's glands. It can be concluded that Ayurvedic medicines used do not act as antacid but improve the secretory status of Brunner's glands involved in the protection against duodenal ulcer.

Effect of vitamin E on lipid peroxidation in buffalo Bubalus bubalis L.

Abstract: Vitamin E significantly (P less than 0.01), inhibited lipid peroxidation as indicated by malonaldehyde (MDA) production and improved significantly (P less than 0.01) motility and percent live spermatazoa of B. bubalis semen. Bulls with higher MDA formation had lower sperm motility and percent live count. Variance due to bulls for all the three parameters were significant (P less than 0.05).

Solasodine levels in Solanum sisymbriifolium Lam.

Abstract: Solasodine content in berries, leaves and stem of S. sisymbriifolium, using three different procedures, was 0.93, 0.73 and 0.23% respectively. Further in chromatogram not only solasodine but three more alkaloids (Rf 0.22, 0.48 and 0.88) were found which could not be identified due to lack of authentic samples.

Effect of dietary fiber from banana (Musa paradisiaca) on metabolism of carbohydrates in rats fed cholesterol free diet.

Abstract: Effect of feeding isolated dietary fiber from M. paradisiaca on the metabolism of carbohydrates in the liver has been studied. Fiber fed rats showed significantly lower levels of fasting blood glucose and higher concentration of liver glycogen. Activity of glycogen phosphorylase, glucose-1-phosphate, uridyl transferase and glycogen synthase was significantly higher while phosphoglucomutase activity showed lower activity. Activity of some glycolytic enzymes, viz. hexokinase and pyruvic kinase was lower. Glucose-6-phosphatase showed higher activity while fructose 1-6 diphosphatase activity was not affected. Glucose-6-phosphate dehydrogenase on the other hand showed higher activity. The changes in these enzyme activities have been attributed due to the effect of higher concentration of bile acids produced in the liver as a result of feeding fiber. Evidence for this has been obtained by studying the in vitro effect of cholic acid and chenodeoxy cholic acid.

Hydrogen production from glucose by Citrobacter freundii.

Abstract: C. freundii, a member of Enterobacteriaceae was isolated from nearby sewage and characterised. With optimum conditions, its hydrogen production capacity and efficiency was tested in synthetic medium containing glucose as carbon and energy source. C. freundii was grown in a 51 fermentor under batch anaerobic conditions. The total production of gas was 8.91 in the volumetric ratio of 63% H2 and 37% CO2 in 11 hr from 30.8 g glucose. From 1 mole of glucose 1.286 mole of hydrogen was produced (YH2/s). The rate of gas production (rQ) and hydrogen production (rH2) was 0.71 and 0.45 1/hr respectively. The strain appears to be a better one for hydrogen production compared to the earlier Citrobacter spp reported.

Xanthine oxidase, superoxide dismutase, catalase and lipid peroxidation in Mastomys natalensis: effect of Dipetalonema viteae infection.

Abstract: Status of xanthine oxidase, superoxide dismutase, catalase and lipid peroxidation, the enzymes metabolizing reactive oxygen intermediates in liver, lungs and spleen of M. natalensis during D. viteae infection was investigated. Xanthine oxidase and lipid peroxidation exhibited stimulation, while superoxide dismutase and catalase showed depression in liver and spleen of the infected animals. The filarial infection therefore appears to create O2 toxicity in these tissues. Lungs, on the other hand was found safe as it possessed elevated xanthine oxidase, superoxide dismutase and catalase. Lipid peroxidation in lungs operated below the control level. The impact of these changes in the establishment and development of the infection has been discussed.

Possible interaction of potassium embelate, a putative analgesic agent, with opiate receptors.

Abstract: The in vivo studies have been carried out in the rat brain for characterization of binding sites for potassium embelate (ex: Embelia ribes) a potent centrally acting analgesic compound. The results indicate that mixed mu and kappa binding sites in the brain may be involved in the analgesic action of this compound.

Biochemical toxicity of hexachlorocyclohexane and its gamma-isomer in albino mice.

Abstract: Dietary hexachlorocyclohexane (HCH) and gamma-isomer of HCH produced significant increase in liver weights of mice. Elevated levels of alanine and aspartate aminotransferases and of alkaline phosphatase in the blood of these animals suggested hepatotoxicity. Hepatic soluble enzymes--aspartate aminotransferase and lactate dehydrogenase--were markedly lowered. Among the hepatic lysosomal enzymes, acid phosphatase and acid cathepsin were increased in the experimental animals. Hepatic glucose-6-phosphatase was lowered by HCH while aldolase activity was increased. Hydrolytic enzymes in small intestine, viz., disaccharidases, lipase, amylase, dipeptidase and phosphatases, were also affected by dietary HCH and gamma-HCH. The results suggested cellular toxicity in hepatocytes of HCH and gamma-HCH fed animals, and also interference in gastrointestinal absorption.

Effect of aspartate and glutamate on experimental myocardial infarction in rats.

Abstract: Cardiac necrosis was produced in rats by administering isoproterenol sulphate (85 mg/kg, sc for 4 days). The myocardial damage was proved by observing the elevated levels of serum aspartate amino-transferase, lactate dehydrogenase and creatine phosphokinase and the changes were confirmed by histopathology of the tissue. Both aspartate and glutamate (100 mg/kg, ip) significantly reduced the elevated levels of these enzymes. The average degree of cardiac necrosis produced in these rats when observed macroscopically and histologically was also found to be significantly reduced on pretreatment with aspartate and glutamate.

In vitro capacitation of goat spermatozoa.

Abstract: Goat epididymal and ejaculated spermatozoa were incubated in Krebs-Ringer bicarbonate buffer containing pyruvate and lactate as energy source. A 3 hr incubation for epididymal and 4 hr for ejaculated spermatozoa was required for the capacitation and acrosome reaction to take place. Calcium is an essential requirement which was needed for motility maintenance/activation and for the initiation of acrosome reaction. A 2-fold increase in cAMP content was measured over 3 hr period of incubation of goat epididymal spermatozoa which was not seen when calcium ions were either omitted or chelated with EGTA. There is thus a definite involvement of Ca2+ ions and cAMP in capacitation and acrosome reaction of goat spermatozoa.

Serum and thyroid tissue lipids in patients with thyroid tumors in euthyroidism.

Abstract: Plasma lipids of 24 euthyroid subjects with thyroid adenoma and non-toxic primary differentiated thyroid carcinoma (papillary and follicular types) were assessed and compared with a similar investigation conducted on 20 normal subjects. A parallel study with thyroid tumor tissues examined the lipid changes which occurred in the same group of patients. These were compared with the picture seen in 5 normal thyroids. The investigations examined the changes in total lipids; total, free and esterified cholesterol; total phospholipids; lecithin; cephalin and sphingomyelin; triglycerides and free fatty acids in both serum and thyroid tissue. Compared with normal subjects, the serum lipids were almost identical except for the concentration of free fatty acids which showed significantly lower values in the group with neoplastic changes. Tissue analysis of the cancerous thyroid however revealed a marked rise in virtually all lipid fractions but the cholesterol seemed to dominate the picture. The differential studies of total phospholipids for thyroid tissue membrane lipids further revealed a significant increase in the lecithin and sphingomyelin components of total phospholipids as well as the esterified cholesterol fraction in thyroid carcinoma. The changes in thyrophospholipids were more marked in females normal thyroids than males. An attempt has been made through evaluation of the results derived from differential lipid studies to elucidate the role of some of the various fractions determined and the possible effect of the changes described on thyroid hormone metabolism.

Effect of anaesthetic ether on lipid peroxidation and superoxide dismutase isozymes of young and adult rat brain.

Abstract: Changes in lipid peroxidation and superoxide dismutase level in rat brain due to single exposure to diethyl ether (anaesthetic) were studied in 100 and 300 day old rats. Enhancement of superoxide dismutase activity was more pronounced in young rat brain, while the reverse was the case with lipid peroxidation. The neurotoxic effects of diethyl ether may involve active oxygen species and superoxide dismutase activity increases as a defensive adaptation.