Effect of a sesquiterpene fromAristolochia indica Linn. on fertility in female mice

Summary A sesquiterpene isolated from the roots ofAristolochia indica (Linn.) was found to exert 100% interceptive activity and 91.7% anti-implantation activity in mice at a single oral dose of 100mg/kg b. wt. No toxic effect was found at the dose levels used.The authors wish to thank Dr S. C. Pakrashi and his associate Mr P. P. Ghosh Dastidar of Medicinal Chemistry Department for isolating the compound for this study. Thanks are also due to Director-General of Indian Council of Medical Research for granting a Junior Research Fellowship to C.S.     

Trichinella spiralis: acceleration and inhibition of cyst calcification in rats.

Daily administration of vitamin D3 (75,000 IU/kg b. wt) for 7 days accelerated Trichinella spiralis cyst calcification in rats with a 14-week-old infection. When disodium ethane-1-hydroxy-1, 1-diphosphonate (EHDP) was administered (50 mg/kg b. wt) from 2 days before until 2 days after vitamin D3 treatment, cyst calcification was inhibited. Thus, the ability to inhibit E. spiralis calcification has demonstrated for the first time.     

Influence of phenobarbital and TCDD on the hepatic metabolism of TCDD in the dog

The influence of phenobarbital and TCDD pretreatment on the formation and biliary excretion of TCDD-metabolites following single doses of 3H-TCDD was investigated. Without pretreatment, 24.5% of the absorbed 3H-TCDD dose was excreted in the bile within 110 h. Phenobarbital did not influence this rate, whereas a single dose of 10 micrograms of unlabeled TCDD/kg b.wt nine days earlier resulted in a doubling of the amount of radioactive material eliminated in the bile (47.4%).     

Effect of methyl ester of aristolic acid fromAristolochia indica Linn. on fertility of female mice

Summary Methyl ester of aristolic acid, a pure compound isolated from the roots ofAristolochia indica (Linn.), was found to exert 100% abortifacient activity at a single oral dose of 60 mg/kg b. wt when administered on 6th or 7th day of pregnancy; 20 and 25% abortifacient effect were observed at the same dose on day 10 and 12, respectively.The authors wish to thank Dr S.C. Pakrashi and his associate Mr P.P. Ghosh Dastidar for the compound. Thanks are also due to the Director General of Indian Council of Medical Research for granting a fellowship to one of them (C.S.).     

Melatonin modulates apomorphine-induced rotational behaviour

Summary Prior melatonin administration (1 and 10 mg/kg b.wt) causes a significant reduction in apomorphine (1 mg/kg b.wt) induced rotational behaviour in both 6-hydroxydopamine and quinolinic acid lesioned rats.     

Effect of the extracts from Aristolochia indica Linn. on interception in female mice.

The crude petroleum ether, chloroform and alcoholic extracts from the roots of Aristolochia indica (Linn.) showed 100% interceptive activity in mature female mice at the single dose of 100 mg/kg body wt. The follow-up studies with the chloroform extract showed the most significant effect in the basic part and two acidic fractions at the single dose levels of 50 mg/kg body wt. No toxic effect was observed at the dose levels used.     

Effect of the extracts fromAristolochia indica Linn. on interception in female mice

Summary The crude petroleum ether, chloroform and alcoholic extracts of the roots ofAristolochia indica (Linn.) showed 100% interceptive activity in mature female mice at the single dose of 100 mg/kg body wt. The follow-up studies with the chloroform extract showed the most significant effect in the basic part and two acidic fractions at the single dose levels of 50 mg/kg body wt. No toxic effect was observed at the dose levels used.The authors are thankful to Mr.P. P. Ghosh Dastidar, Medicinal Chemistry Division for the plant extracts. Thanks are also due to Indian Council of Medical Research and Council of Scientific and Industrial Research for granting scholarships to two of them (B.C. and A.D.) and to Prof.R. N. Chakravarti, Director of the Institute for encouragement.     

Influence of phenobarbital and TCDD on the hepatic metabolism of TCDD in the dog

Summary The influence of phenobarbital and TCDD pretreatment on the formation and biliary excretion of TCDD-metabolites following single doses of³H-TCDD was investigated. Without pretreatment, 24.5% of the absorbed³H-TCDD dose was excreted in the bile within 110 h. Phenobarbital did not influence this rate, whereas a single dose of 10 g of unlabeled TCDD/kg b.wt nine days earlier resulted in a doubling of the amount of radioactive material eliminated in the bile (47.4%).     

An escape phenomenon from water and sodium retention induced by propranolol in rats

Rats given a daily dose of propranolol 45 mg/kg b.wt retain water and sodium for 4 days, escaping during the 5th and 6th days in which their excretions are larger than basal values. Afterwards, in the period studied, they make a new retention and clearing is less accentuated. No relationship could be found between these retentions and plasma renin activity or renal renin content.     

Trichinella spiralis: Acceleration and inhibition of cyst calcification in rats

Summary Daily administration of vitamin D₃ (75,000 IU/kg b.wt) for 7 days acceleratedTrichinella spiralis cyst calcification in rats with a 14-week-old infection. When disodium ethane-1-hydroxy-1,1-diphosphonate (EHDP) was administered (50 mg/kg b.wt) from 2 days before until 2 days after vitamin D₃ treatment, cyst calcification was inhibited. Thus, the ability to inhibitT. spiralis calcification has been demonstrated for the first time.Supported in part by EKU faculty research grant No. 03-05.Much appreciation goes to Dr Gordon S. Hassings and the Proctor and Gamble Company, Miami Valley Laboratories, Cincinnati, Ohio USA for providing the EHDP used in this study.     

A new drug against Paragonimus infection

Summary An oral dose of 50–100 mg/kg b.wt of a new anthelmintic, albendozole, for 2–3 weeks killed adult flukes and stopped shedding of ova of Paragonimus kellicotti in experimentally infected cats. No clinical signs related to treatment were recognized. This low toxicity of albendozole may be useful in treating human paragonimiasis.     

Ascorbic acid content of neotropical plant parts available to wild monkeys and bats

Summary The ascorbic acid content of foliage available to wild primates and bats in Panama (in transition between wet and dry seasons) was lower than that of temperate zone foliage but higher than that of most fruits and vegetables. Intakes of ascorbic acid (mg/kg b.wt/day) by wild primates and frugivorous bats in Panama are much greater than that of most human populations.     

An escape phenomenon from water and sodium retention induced by propranolol in rats

Summary Rats given a daily dose of propranolol 45 mg/kg b.wt retain water and sodium for 4 days, escaping during the 5th and 6th days in which their excretions are larger than basal values. Afterwards, in the period studied, they make a new retention and clearing is less accentuated. No relationship could be found between these retentions and plasma renin activity or renal renin content.Acknowledgments. The authors thank Mrs Inmaculada Millás for excellent technical assistance and Maria Isabel Navajos for secretarial help.     

Ascorbic acid content of neotropical plant parts available to wild monkeys and bats

The ascorbic acid content of foliage available to wild primates and bats in Panama (in transition between wet and dry seasons) was lower than that of temperate zone foliage but higher than that of most fruits and vegetables. Intakes of ascorbic acid (mg/kg b.wt/day) by wild primates and frugivorous bats in Panama are much greater than that of most human populations.     

Lowering of liver acetaldehyde but not ethanol concentrations by pretreatment with taurine in ethanol-loaded rats

A rise in blood and liver acetaldehyde concentrations following ethanol loading (1.5 g/kg b.wt) was significantly reduced when rats were pretreated orally with taurine (0.5 g/kg), a potent in vitro activator of yeast aldehyde dehydrogenase. This taurine pretreatment produced a 4-fold increase in liver taurine content.     

Lowering of liver acetaldehyde but not ethanol concentrations by pretreatment with taurine in ehtanol-loaded rats

Summary A rise in blood and liver acetaldehyde concentrations following ethanol loading (1.5 g/kg b.wt) was significantly reduced when rats were pretreated orally with taurine (0.5 g/kg), a potent in vitro activator of yeast aldehyde dehydrogenase. This taurine pretreatment produced a 4-fold increase in liver taurine content.     

The effect of melatonin on the formation of gastric stress lesions in rats

Summary Prior melatonin administration (1,5 and 10 mg/kg b. wt) causes a significant reduction in gastric ulceration induced in male rats by restraint immobilization in the presence of low temperatures.     

Stimulation of gastric secretion by prostaglandin F2 alpha in rats.

In rats with chronic gastric fistulas, prostaglandin F2 alpha stimulated the gastric acid secretion in graded doses of 50, 100, 200 and 400 microgram/kg b.wt, while higher doses above 1 mg/kg b.wt tended to inhibit significantly. The gastric antisecretory effect of prostaglandin E1 could not be altered or modified by subsequent treatment of prostaglandin F2 alpha, while the latter alone without any prior treatment of the former, stimulated output of gastric juice, HCl and pepsin without significantly affecting the concentration of these components.     

Monoaminoguanidine prevents sorbitol accumulation, nonenzymatic protein glycosylation and development of kidney lesions in diabetic rats

Monoaminoguanidine administration (25 mg/kg b.wt, i.p. for 14 weeks) to alloxan diabetic rats (blood glucose greater than or equal to 250 mg/dl) decreased the nonenzymatic protein glycosylation and sorbitol levels. It prevented development of Armanni-Ebstein tubular lesions, pathological changes in the glomerular capillary tufts and glomerular basement membrane thickening in the kidney.     

Prostaglandin analogue protects pancreatic B-cells against cyclosporin A toxicity

Cyclosporin A toxicity on pancreatic B-cells and its prevention by rioprostil, a prostaglandin E1 analogue, were studied in the model of the isolated perfused pancreas of rats treated with both compounds for 8 days. At toxic doses of cyclosporin (10 and 20 mg/kg b.wt), the B-cells showed severe hydropic degeneration of the endoplasmatic reticulum and slight degranulation of the B-cells. Accordingly, the insulin secretion was markedly impaired. Administration of rioprostil ameliorated the insulin secretion significantly, but not the ultrastructural changes. At therapeutic levels of cyclosporin (5 mg/kg b.wt), the hydropic degeneration and the drop in insulin secretion were completely prevented by rioprostil. This observation might have therapeutic implications in the treatment of patients, in particular those undergoing pancreatic transplantation.