摘要:

AbstractThe aqueous fraction of the ethanol extract of the root ofCissampelos sympodialis, reduced the spontaneous tone, and inhibited the contractions induced by submaximal concentrations of carbachol, histamine, prostaglandin F2αand substance P, in guinea‐pig tracheal preparations. The fraction was approximately equipotent to aminophyl‐line and the IC50values of the above agents varied from 13.9 to 95.5 μg/mL, depending on the agonist used. In concentrations ranging from 1–100 μg/mL, the fraction also increased the intracellular levels of cyclic adenosine monophosphate in guinea‐pig bronchoalveolar leucocytes. It is proposed that the combined effects on smooth muscles and on leucocytes indicate a pharmacological basis for the use of the plant

ISSN:0951-418X    

DOI:10.1002/ptr.2650090702

出版商:John Wiley&Sons, Ltd.    

年代:1995

数据来源: WILEY

摘要:

AbstractThe effects of subcutaneous (s.c.) administration of processed shilajit (PS) alone and in combination with insulin (s.c.) on plasma glucose levels (PGL) were determined in either sex of streptozotocin‐induced diabetic (SID) rats. PS (50 μ/kg; s.c.) did not alter plasma glucose levels in SID rats. Insulin (0.25‐1.0 U/kg; s.c.), dose‐dependently produced hypoglycaemia in SID rats. PS (50 μg/kg; s.c.) potentiated and prolonged the hypoglycaemic action of insulin when administered concurrently. Chronic administration of PS (0.1–10 mg/kg; b.i.d. for 10 days; i.p.) had no influenceper seon plasma glucose levels. Chronic administration of PS (1.0 mg/kg; b.i.d. for 10 days; i.p.) prevented the streptozotocin (STZ)‐induced diabetes in rats, whereas a relatively lower (0.1 mg/kg; b.i.d. for 10 days; i.p.) and significantly higher dose (10 mg/kg; b.i.d. for 10 days; i.p.) of PS had no influence on the STZ‐induced diabetes. The results suggest that administration of PS along with insulin would potentiate the insulin‐induced hypoglycaemia, and chronic administration of a carefully determined dose of PS would inhibit the development of STZ

ISSN:0951-418X    

DOI:10.1002/ptr.2650090703

出版商:John Wiley&Sons, Ltd.    

年代:1995

数据来源: WILEY

摘要:

AbstractFrom latex ofExcoecaria bicolor(Euphorbiaceae) four TLC‐homogeneous fractions highly enriched in diterpene esters were obtained (F1–F4). Fraction F3 by NMR was found to be a mixture of 9,13,14‐orthoester‐20‐esters (1a) of 5β‐hydroxyresiniferonol‐6α,7α‐epoxide (1). Alkaline transesterification yielded from 1a a mixture of 5β‐hydroxyresiniferonol‐6α,7β‐epoxide‐9,13‐14‐orthoesters (1f) carrying unsaturated orthoester groups as a TLC‐homogeneous material (final isolation ofExcoecariafactors B1/B2, B3 and B4). The transesterification mixture also contained, according to GC‐MS, methyl n‐carboxylates corresponding to the even numbered C22−C30acids from 20‐positions in 1a. Fraction F4 by NMR contained molecular species (2a) structurally closely related to 1a, carrying 5β,12β‐dihydroxyresiniferonol‐6α, 7α‐epoxide (2) as the parent alcohol. From 2a, by alkaline transesterification, a two‐component mixture ofExcoecariafactors B5/B6, i.e. 5β,12β‐dihydroxy‐resiniferonol‐6α,7α‐epoxide‐9,13,14‐ortho(2,4,6‐hexadecatrienoate)/‐(2,4,6,8‐hexadecatetraenoate) (2b/2c) was obtained. GC‐MS of the transesterification mixture revealed methyl n‐carboxylates corresponding to even numbered C16‐C16acids from 20‐positions in 2a (omitting C18and C20). Fractions F1 and F2 by alkaline transesterifications yielded 12‐deoxyphorbol (3) and its 13‐(3,5‐tetradecadienoate) 3b (Excoecariafactor B7). Moreover 4,12‐dideoxy(4α)phorbol (4), its 13‐(3,5‐tetradecadienoate) 4b and the natural 4‐epimer of 4b 4,12‐dideoxyphorbol‐13‐(3,5‐tetradecadienoate) (5a) (newExcoecariafactor B8) were obtained. GC‐MS of the transesterification mixtures revealed mainly methyl n‐carboxylates corresponding to even numbered C16‐C30acids. Thus the latex and the fractions F1 and F2 contain 13,20‐diesters of the parent alcohols 12‐deoxyphorbol (3) and 4,12‐dideoxyphorbol (5). 4,12‐dideoxy(4α)phorbol (4) and its derivatives may be considered artifacts from alkaline epimerization of 5. The daphnane typeExcoecariafactors B1‐B6 are structurally very closely related to diterpenes such as yuanhuacine occurring in certainDaphneandWikstroemiaspecies. Daphnane type esters of this kind are currently used routinely in China for fertility regulation. Similarly, daphnane and tigliane typeExcoecariafactors p

ISSN:0951-418X    

DOI:10.1002/ptr.2650090704

出版商:John Wiley&Sons, Ltd.    

年代:1995

数据来源: WILEY

摘要:

AbstractThe effect of an aqueous‐methanol extract ofBerberis aristatafruits (Berberidaceae) was investigated against paracetamol‐ and CCl4‐induced hepatic damage. Paracetamol produced 100% mortality at a dose of 1 g/kg in mice while pre‐treatment of animals with crude extract (500 mg/kg) reduced the death rate to 10%. Pre‐treatment of rats with fruit extract (500 mg/kg, orally twice daily for 2 days) prevented (p<0.05) the paracetamol (640 mg/kg) as well as CCl4(1.5 mL/kg)‐induced rise in serum transaminases (GOT and GPT). Post‐treatment with three successive doses of extract (500 mg/kg, 6h) restricted the hepatic damage induced by acetaminophen (p0.05). Plant extract (500 mg/kg) caused significant prolongation (p<0.01) in pentobarbital (75 mg/kg)‐induced sleep as well as increased strychnine‐induced lethality in mice suggestive of inhibitory effect on microsomal drug metabolizing enzymes (MDME). These results indicate that the crude extract ofBerberis aristatafruits exhibits hepatoprotective action partly through MDM

ISSN:0951-418X    

DOI:10.1002/ptr.2650090705

出版商:John Wiley&Sons, Ltd.    

年代:1995

数据来源: WILEY

摘要:

AbstractThe pharmacological effects of the dichloromethanol and methanol extracts obtained from leaves and stems ofGenista patensDC were analysed inin vitroandin vivomodels. Both extracts showed low acute toxicity (LD50>3 g/kg), CNS depressor and antiinflammatory activity, and similar analgesic effect in models of chemical and thermal stimulation. Furthermore, the dichloromethanol extract (1–20 mg/kg) induced a pronounced dose‐dependent decrease on blood pressure. On isolated organs, the dichloromethanol extract (1, 10, 100 μg/mL) shifted the concentration‐effect curve to the right for ACh and reduced the Emaxinduced by histamine without modifying responses induced by noradrenaline and ser

ISSN:0951-418X    

DOI:10.1002/ptr.2650090706

出版商:John Wiley&Sons, Ltd.    

年代:1995

数据来源: WILEY

摘要:

AbstractRats raised on a diet containing 0.5% adenine showed atrophy of the testes and retrogressive degeneration of the convoluted seminiferous tubules. The development of spermatids was suppressed, and the cell count decreased. In these rats, the activity of 3β‐hydroxysteroid dehydrogenase was markedly decreased, and the blood levels of testosterone and oestradiol were also very low. However, in rats that were also given You‐Gui‐Wan, retrogressive degeneration of the testes was milder, and the blood levels of testosterone and oestradiol were higher, indicating the beneficial effects of You‐Gui‐Wan on the histomorphology of

ISSN:0951-418X    

DOI:10.1002/ptr.2650090707

出版商:John Wiley&Sons, Ltd.    

年代:1995

数据来源: WILEY

摘要:

AbstractSeventeen fractions of extracts obtained from 11 Tanzanian medicinal plants, which had previously been shown to possess a high antimalarial activityin vitrowere submitted to the 4‐day suppressive test inPlasmodium berghei‐infected mice, and were investigated for cytotoxic activity in human carcinoma cell linesin vitro.Several fractions administered orally to the mice (500 mg/kg body weight/day) produced a significant reduction of parasitaemia. The most effective plant fractions investigated were those of the root and stem bark ofMaytenus senegalensis(90% and 63% suppression of parasitaemia, respectively) and of the roots ofCissampelos mucronata(59% suppression). Highest cytotoxic activities were found with all fractions ofMaytenus senegalensis(IC501 μg/mL) and with the PE fraction of the roots ofSalacia madagascariensis(median IC50=1.2 μg/mL for HT 29 and 2.3 μg/mL f

ISSN:0951-418X    

DOI:10.1002/ptr.2650090708

出版商:John Wiley&Sons, Ltd.    

年代:1995

数据来源: WILEY

摘要:

Abstract5,7,2′,4′‐Tetrahydroxy‐8‐lavandulyl‐flavanone, isolated fromSophora exigua, completely inhibited the growth of 21 strains of methicillin‐resistantStaphylococcus aureus(MRSA) at concentrations of 3.13–6.25 μg/mL. The anti‐MRSA effect was based on bactericidal action. In combinations of the flavanone with vancomycin, minocycline and rifampicin, the fractional inhibitory concentration indices were 0.90, 0.88 and 0.85, respectively, indicating partial synergistic effects with anti‐MRSA antibiotics. The proposed flavanone would be a potent phytotherapeutic agent aga

ISSN:0951-418X    

DOI:10.1002/ptr.2650090709

出版商:John Wiley&Sons, Ltd.    

年代:1995

数据来源: WILEY

摘要:

AbstractThe aqueous extract ofMelothria maderaspatanais used by traditional medical practitioners to treat jaundice in man. The effect ofMelothria maderaspatanaextract on damage induced in freshly isolated rat hepatocytes by D‐galactosamine and tert‐butyl hydroperoxide (TBH) has been investigated. On incubation of hepatocytes with galactosamine or TBH in the presence of the plant extract, a significant dose‐dependent protection against hepatocyte damage was observed, with maximum protection at a concentration of 500 μg/mL. At this concentration the galactosamine‐induced release of lactate dehydrogenase (LDH) and aspartate amino‐transferase (AST) were reduced by 40.7% ± 4.2% and 37.7% ± 6.1% respectively, compared with control incubations. The TBH‐induced lipid peroxidation (estimated from malondialdehyde production) was decreased by 26.0 ± 3.7% together with a 38.4% ± 4.4% and 40.8 ± 7.6% reduction in the release of cellular LDH and AST respectively into the incubation medium. On post‐treatment with the plant extract the protective activity was found to decrease with increase in time of exposure of the cells to either of the toxins. The direct protective effects ofMelothriaextract on hepatocytes support the use of this plant

ISSN:0951-418X    

DOI:10.1002/ptr.2650090710

出版商:John Wiley&Sons, Ltd.    

年代:1995

数据来源: WILEY

摘要:

AbstractAfter partial hepatectomy in rats certain biochemical parameters in liver registered a maximal increase at varying periods of time, glutamate oxaloacetate transaminase (GOT), glutamate pyruvate transaminase (GPT) (6 h), lipid peroxides (12 h); DNA, RNA (24 h) and acid ribonuclease, acid phosphatase (48 h). In contrast, other parameters registered a maximal decrease after 6 h (glycogen) or 24 h (total proteins, cytochrome P450and cytochrome b5). Subsequently, all these parameters started recovering towards their normal values which were attained in all parameters measured except RNA, glycogen, cytochrome h5and acid ribonuclease. When partial hepatectomy was performed in rats fed 12 mg/kg body wt picroliv (an iridoid glycoside fraction ofPicrorhiza kurroa) once daily for 7 days before killing, there was no significant difference in the time or degree of maximal changes but the rate of recovery in most of the biochemical parameters was faster. These results indicate that picroliv stimulated regeneration of liver.

ISSN:0951-418X    

DOI:10.1002/ptr.2650090711

出版商:John Wiley&Sons, Ltd.    

年代:1995

数据来源: WILEY