Potentiating action of Datura metel Linn. Root extract on rat intestinal cholinesterase

Datura metel Linn. leaf extract which is known to contain scopolamine, a tropane alkaloid, was found to inhibit rat intestinal cholinesterase in vitro. The inhibition could not be reversed with higher concentrations of cholinesterase substrate. Whereas Dutura metel root extract was found to activate cholinesterase enzyme activity at optimal or higher substrate concentrations. With root and leaf extract together, the cholinesterase activity level at higher concentrations of substrate, was elevated compared with the inhibitory effect of Datura leaf extract alone, suggesting a potentiating action of Datura root extract on cholinesterase.     

Spasmogenic effect of Datura metel root extract on rat uterus and rectum smooth muscles

The effect of Dautura metel leaf and root extracts, scopolamine and acetylcholine was studied on isolated smooth muscle preparations. Datura metel leaf extract and scopolamine showed antispasmodic effects, whereas Datura metel root extract and acetylcholine caused contracture in isolated rat uterus and rectum whole muscle. This suggests the presence of a spasmogenic factor in Datura metel root extract.     

Effects of leaf and root extracts of Nauclea latifolia on purinergic neurotransmission in the rat bladder

The leaf and root parts or their combination of Nauclea latifolia were separately extracted and their pharmacological effects on purinergic transmission in the bladder investigated. The leaf extract was very potent in potentiating purinergic neurotransmission by potentiating ATP induced contractions. These actions were more pronounced than the depression of potassium chloride evoked contraction of the bladder. The root extract depressed purinergic contraction of the bladder by a direct depressant action on the bladder smooth muscle since it did not modify ATP induced contractions. The leaf and root extracts antagonized each other when combined together. It is concluded that the leaf and root extracts of N. latifolia possess interesting pharmacological actions on the bladder.     

Effect of Extract of Leaf and Seed of Piper guineense on Some Smooth Muscle Activity in Rat,Guinea-pig and Rabbit

Extracts of the leaf and seed of Piper guineense were separately prepared and their pharmacological effects screened using smooth muscle of the gastrointestinal tract and uterus. The leaf extract enhanced both the frequency and tone of spontaneous contractions of rabbit jejunum and induced contraction of guinea-pig ileum, which were blocked by atropine. The seed extract had the opposite effect on rabbit jejunum, an inhibition which was antagonized by prazocin, and little or no effect on guinea-pig ileum. Both extracts had a stimulant effect on rat uterine muscle, the seed extract to a lesser extent.     

Effects of stembark and leaf extracts of Bridelia ferruginea on skeletal muscle

The ethanolic extracts of the leaves and stembark of Bridelia ferruginea were separately investigated for their effects on skeletal muscle using the phrenic nerve-hemidiaphragm muscle preparation from rats. The bark extract inhibited twitch tension induced by direct electrical stimulation (muscle) (MS) but not indirect electrical stimulation (nerve) (NS) of the diaphragm. It inhibited tetanus tension to both nerve (TNS) and muscle stimulation (TMS), had no effect on K⁺-induced contracture and reduced the minimal fusion frequency (MFF). The leaf extract had no effect on twitch tension to NS and MS or K⁺-induced contracture but increased tetanus tension to TNS or TMS as well as MFF. These findings suggest that the bark extract does not affect influx of extracellular Ca²⁺ but inhibits the intracellular mobilization of Ca²⁺. The leaf extract also had no effect on influx of extracellular Ca²⁺ but most likely facilitated the intracellular mobilization of Ca²⁺. Thus, the intracellular action of the bark extract is opposite to that of the leaf extract.     

檀香不同萃取物对豚鼠离体肠平滑肌收缩的影响

目的:观察檀香不同萃取物对豚鼠离体回肠平滑肌收缩的影响,探讨其作用机制.方法:利用BL-420F生物机能实验系统,在HW-400S恒温平滑肌浴槽中,37℃下观察檀香不同萃取物对豚鼠离体回肠运动功能的影响.结果:檀香水提液乙醚萃取物、檀香水提液乙酸乙酯萃取物、檀香醇提液乙醚萃取物、檀香醇提液乙酸乙酯萃取物对豚鼠离体肠自主运动有抑制作用(P＜0.01),表现为振幅减低;檀香水提液乙醚萃取物、檀香水提液乙酸乙酯萃取物、檀香醇提液石油醚萃取物、檀香醇提液乙醚萃取物、檀香醇提液乙酸乙酯萃取物对乙酰胆碱( Ach)造成的豚鼠离体肠痉挛状态有拮抗作用(P＜0.01),表现为振幅减低;檀香水提液乙酸乙酯萃取物对阿托品造成的松弛状态有明显的协同作用(P＜0.01),表现为振幅减低.结论:檀香不同萃取物对豚鼠离体肠平滑肌有抑制作用.     

Neem (Azadirachta indica) treatment decreases spontaneous motor activity in rats: implications for its central sedative action

The administration of a crude steroidal extract of neem (Azadirachta indica A. Juss) leaf significantly decreased the total spontaneous motor activity (SMA) scores in rats receiving either 100 mg/kg body weight (i.p.) twice per week for 6 weeks (p <0.01) or a single dose (p <0.05), indicating that neem may have a sedative effect on rats. Single dose (acute) treatment also significantly decreased (p <0.01) the amplitude of the peak twitch force of the gastrocnemius muscle in vivo, but the neem extract exerted no significant effect on amplitude or conduction velocity of the compound action potential of the toad sciatic nerve preparation in vitro. It is therefore concluded that the depression of the SMA may be due to an effect of neem on the central nervous system and/or muscle strength, but not on peripheral nerve conduction. © 1997 John Wiley & Sons, Ltd.     

Guava leaf extract and topical haemostasis

The effects of guava leaf extract on the bleeding time and the three main mechanisms of haemostasis: vasoconstriction, platelet aggregation and blood coagulation, were investigated. The water extract of guava leaves did not shorten bleeding times in rats. Guava leaf extract potentiated the vascular muscle contraction induced in rabbits by phenylephrine, and when given alone it stimulated human platelet aggregation in vitro in a dose-dependent manner. On the other hand, it significantly prolonged blood coagulation; activated partial thromboplastin time (APTT) test (p < 0.05). The higher the concentration of the extract, the longer APTT was observed. Thus, a water extract of guava leaves showed ambiguous effects on the haemostatic system. Guava leaf extract did not affect bleeding times, it stimulated vasoconstriction and platelet aggregation but it inhibited blood coagulation. Therefore, guava leaf extract is not recommended as a haemostatic agent.     

CNS depressant effects,anti-inflammatory activity and anti-cholinergic actions of Santolina chamaecyparissus extracts

The pharmacological activity of several extracts together with the lyophilized infusion of S. chamaecyparissus ssp. squarrosa were investigated. The lethal dose 50% (LD₅₀), effect on animal metabolism, mechanical and thermic analgesia and spontaneous, anti-inflammatory, and anti-ulcer activity have been determined. Studies on isolated organs (rat duodenum and rat uterus) were also carried out. The hexanic and chloroformic extracts were potent antagonists of the thermic analgesia test; the former extract was also active in the mechanical analgesia test. The chloroformic extract and, to a lesser extent, the ethyl acetate extract and lyophilized infusion demonstrated noteworthy activity as anti-inflammatory agents. No extract produced an ulcerogenic effect. The hexanic extract had the highest inhibitory effect on ACh induced contraction of rat duodenum and the ethyl acetate extract of oxytocin induced contraction of rat uterus.     

Effects of an aqueous extract of Terminalia arjuna on isolated rat atria and thoracic aorta

Terminalia arjuna (Combretaceae) is used traditionally in ayurveda, to treat a variety of cardiovascular disorders. The aims of this study were to characterize the positive inotropic effect of the aqueous extract of T. arjuna bark in isolated paced rat left atria and to study its effects on a vascular smooth muscle preparation, the rat thoracic aorta. The crude and semipurified aqueous extracts produced a positive inotropic effect of rat atria and the maximum contraction was comparable to that produced by isoprenaline. The positive inotropic effect of the extract was completely blocked by a β-adrenoceptor blocker, propranolol, and an uptake-1 blocker, cocaine. In precontracted aorta, the aqueous extract produced a contraction followed by relaxation. Propranolol did not block the relaxant effect of the aqueous extract. It is concluded that the positive inotropic effect of the aqueous extract was mediated via an action on β₁-adrenoceptors and was likely to be due to the release of noradrenaline from the sympathetic nerve endings. The vasorelaxant effect of the extract, however, was not mediated via an action on β₂ adrenoceptor.     

Panax ginseng extract improves scopolamine-induced deficits in working memory performance in the T-maze delayed alternation task in rats

The effects of Panax ginseng water extract on spatial working memory disruption induced by scopolamine were examined using a T-maze delayed alternation task in rats. Scopolamine (0.025–0.1 mg/kg, i.p.) dose-dependently impaired the maze performance, and physostigmine (0.4 mg/kg) significantly reversed the scopolamine (0.1 mg/kg)-induced performance deficits. Ginseng extract (0.5–4.0 g dried root/kg) orally administered 60 min before testing dose-dependently improved the maze performance disrupted by scopolamine (0.1 mg/kg). Ginseng extract given for 7 days in drinking water (2.0 and 4.0 g/kg/day) also exhibited dose-dependent reversal of the scopolamine-induced performance deficits. These data indicate the beneficial effects of ginseng extract on spatial working memory in rats.     

Effects of leaf extract of Caesalpinia bonduc (Caesalpiniaceae) on the contractile activity of uterine smooth muscle of pregnant rats

The calcium dependency and the cholinergic effect of the leaf extract of Caesalpinia bonduc Roxb. (Caesalpiniaceae) was studied in isolated pregnant rat myometrium preparations. Isometric contractions were recorded. The extract (Cebo) increased the contractile force in the isolated strips in a concentration-dependent manner. The effects were comparable to those obtained with acetylcholine. Contractions induced by Cebo or acetylcholine were inhibited in the presence of atropine. The stimulating action of Cebo on the contractile responses of isolated myometrium preparations inhibited by atropine may be mediated by cholinergic receptors. In calcium-free solution Cebo induced a tonic contraction (contracture) of the muscle. Moreover, in high-potassium calcium-free solution Cebo caused contracture of the uterine smooth muscle. Cebo was still able to elicit contractions in calcium-free solution containing EDTA or EGTA. These findings suggest the existence of cholinergic receptors sensitive to Cebo which could influence the influx of calcium (phasic contraction) and mobilization of calcium from cellular stores (tonic contraction), both of which are responsible for the increase of contractile activity and development of the contracture of uterine smooth muscle.     

Preparation and Evaluation of a Herbal Uterine Tonic

A herbal uterine tonic was prepared using an aqueous extract of Ficus glomerata , Saraca indica and Woodfordia floribunda . This tonic was evaluated by studying its effect on the normal, oestrogen pretreated and uterine tonic pretreated rat uterus. It produced tonic contraction of the oestrogen pretreated uterus similar to oxytocin. It was also studied on smooth muscle using guinea-pig ileum. The extract was found to have no effect on this preparation. From the toxicological studies the tonic was found to be nontoxic. The formulation may be useful to treat uterine disorders.     

Extract of gravel root (rhizome of Eupatorium purpureum) inhibits integrin-dependent U937 cell adhesion

The effect of the antirheumatic herbal drug, gravel root (rhizome of Eupatorium purpureum), was investigated on integrin-dependent U937 cell adhesion to endothelial cells and extracellular matrix protein, fibronectin. In the presence of gravel root extract (6.3–200 μg/mL), U937 cells lowered their capacity for phorbol myristate acetate (PMA)-mediated adhesion to tumour necrosis factor-α (TNF)-activated endothelial cells or ICAM-1 coated plates. Similarly, the PMA mediated, LFA-1-dependent, homotypic cell aggregation in U937 cells was potently inhibited by gravel root extract. The α₄β₁ and α₅β₁-mediated adhesion of unstimulated U937 cells to fibronectin coated plates was also inhibited by gravel root extract. Neither the TNF-induced enhancement of expression of ICAM-1 on endothelial cell surface nor the TNF-induced endothelial adhesiveness to U937 cells was, however, inhibited by gravel root extract. Since all concentrations of gravel root extract tested failed to alter the proliferation of U937 cells, the observed activity was unlikely to be due to nonspecific suppression of cells. © 1998 John Wiley & Sons, Ltd.     

杜仲叶提取物所含四种主要成分体外抗非酒精性脂肪肝活性研究＊

目的 研究杜仲叶所含4种主要成分体外抗非酒精性脂肪肝（Non-alcoholic fatty liver disease，NAFLD）活性。方法 首先用UPLC-MS检测杜仲叶提取物中绿原酸、杜仲苷、京尼平苷酸、车叶草苷含量；以HepG2细胞为载体，建立NAFLD细胞模型，设正常组、模型组、绿原酸组、杜仲苷组、京尼平苷酸组、车叶草苷组；油红O染色检测细胞内脂质；微量法检测细胞内甘油三酯（Triglyceride，TG）、胆固醇（Total cholesterol，TC）、高密度脂蛋白（High-density lipoprotein cholesterol，HDL-C）、低密度脂蛋白（Low-density lipoprotein cholesterol，LDL-C）含量；微量法检测细胞培养液中谷草转氨酶（Aspartate aminotransferase，AST）、谷丙转氨酶（Alanine aminotransferase，ALT）含量。结果 杜仲叶提取物主要含绿原酸、杜仲苷、京尼平苷酸和车叶草苷，其中京尼平苷酸的含量最高；杜仲叶提取物所含四种主要成分可明显降低细胞内TG、TC、LDL-C含量，其中京尼平苷酸效果最为显著；绿原酸、杜仲苷，京尼平苷酸可显著降低细胞培养液中AST、ALT含量，其中京尼平苷酸效果最好。结论 杜仲叶提取物所含四种主要成分可不同程度降低HepG2细胞内脂质含量，其中京尼平苷酸效果较好。     

Terminalia arjuna extract modulates the contraction of rat aorta induced by KCl and norepinephrine

The bark of Terminalia arjuna is in clinical use for the management of cardiovascular disorders in India. The objective of this study was to investigate the contractile response induced by the extract on rat aorta, a vascular smooth muscle. Terminalia arjuna relaxed the contraction, induced by both KCl (60 mM ) and norepinephrine (NE, 3 μM ). Inhibition was more prominent (80%) in the NE induced contraction than the KCl induced contraction (30%). Under similar conditions diltiazem, a calcium channel blocker (Dz, 1.0 μM ), inhibited 68% of the KCl induced and 30% of NE induced contraction. Thus it appears that the action of Terminalia arjuna extract differs from that of diltiazem in that it is more specific for alpha-adrenergic receptor agonists. It indirectly inhibited the contraction induced by norepinephrine by acting on K (Ca) channel by hyperpolarizing the smooth muscle membrane.     

胡颓子叶对豚鼠离体气管平滑肌收缩功能的影响

目的 研究胡颓子叶乙醇提取物正丁醇部位(胡颓子叶正丁醇部位)对正常及多种致痉剂诱导的豚鼠气管平滑肌收缩功能的影响.方法 制备豚鼠离体气管平滑肌螺旋条,在其正常状态下以及用乙酰胆碱、组胺、氯化钾、无钙下乙酰胆碱诱导细胞内钙释放和高钙下诱发细胞外钙内流条件下,观察胡颓子叶正丁醇部位对离体气管张力的影响.结果 胡颓子叶正丁醇部位对静息状态下的豚鼠离体气管平滑肌有明显的舒张作用,使乙酰胆碱和组胺的量效曲线发生明显右移,抑制加入高钾或高钙后引发细胞外钙内流导致的收缩.结论 胡颓子叶正丁醇部位能明显抑制正常状态及多种致痉剂诱发的豚鼠气管平滑肌收缩.     

Effect of Terminalia arjuna extract on KCl induced contractions in the rat vas deferens

Experiments were carried out to elucidate the effects of extracts from Terminalia arjuna on potassium chloride (160 mM) induced contraction in smooth muscle. The petroleum ether extract did not exhibit a response, whereas the preincubation of tissue with the alcoholic extract inhibited contraction. Experimental approaches, described here, lead to the speculation that T. arjuna may impart its action through the modulation of Ca²⁺ ions across the cellular membrane.     

Genotoxic and antigenotoxic effects of Hemidesmus indicus R. Br. root extract in cultured lymphocytes

Aim of the study

The genotoxic and antigenotoxic potential of the ethanolic extract of Hemidesmus indicus roots were evaluated in cultured human lymphocytes using cisplatin as the positive mutagen.

Materials and methods

Cytogenetic damage and cytotoxicity were determined in cells exposed to different doses of the extract, ranging from 2 to 32 μg/ml of culture medium, either alone or together with cisplatin.

Results

There was a significant reduction in cisplatin-induced frequencies of sister chromatid exchanges, chromosome aberrations and micronucleated binucleate cells at the lower concentrations of 4 and 8 μg/ml (P < 0.05). However, the extract by itself reduced the proliferative rate index, mitotic index and cytokinesis-block proliferative index (P < 0.05). Further, a significant increase in the percentage of chromosome aberrations was noticed at the higher concentrations.

Conclusion

Hemidesmus indicus root extract possesses significant genoprotective effect at the lower concentrations although it is cytotoxic and probably genotoxic at higher doses.     

Confirmatory in vivo Electrodiagnostic and Electromyographic Studies for Neuromuscular Junctional Blocking Action of Cleistanthus collinus Leaf Extract in Rat

Detailed electromyographic and electrodiagnostic studies were made on sciatic nerve–anterior tibialis muscle preparations in rat in vivo for the first time to confirm the neuromuscular junctional (NMJ) blocking action of Cleistanthus collinus leaf extract (CCLE) and the transient reversal of NMJ blockade by neostigmine. A sublethal dose of 175 mg dry leaf powder/kg body weight of rat caused NMJ blockade confirmed by a decremental response in nerve evoked compound muscle action potentials (NCMAPs). The study suggests the action of the toxic plant extract on acetylcholine (ACh) receptor sites. Muscle evoked compound muscle action potentials (MCMAPs) showed negligible decremental response suggesting the action at the NMJ level only and not on muscle excitation and contractility. The CCLE poisoning revealed a specific diagnostic EMG pattern which might be of help to clinicians in diagnosing Cleistanthus poisoning. The studies confirm that the leaf extract contains a proven and promising new NMJ blocker.