Evaluation of the calcium-antagonist, antidiarrhoeic and central nervous system activities of Baccharis serraefolia.
Baccharis serraefolia is a widely used plant to treat diarrhoea in Mexican traditional medicine. Although the methanolic extract of this plant has shown an important dose-dependent spasmolytic activity, its underlying mechanism has not been studied. In the present work, the methanolic extract of B. serraefolia significantly delayed the onset of tonic seizures induced by strychnine and pentylenetetrazol; besides, it diminished the death rate and number of animals that exhibited convulsions. It produced potentiation of the hypnotic effect of pentobarbital. Oral administration produced an inhibition of gastrointestinal transit in mice as effective as that produced by loperamide. As to the effect on smooth muscles, the active extract produced an inhibition of contraction induced electrically, which could not be reversed by naloxone. The calcium concentration-contraction curve showed a rightward displacement when the extract was added to isolated guinea pig ileum depolarized with high K+ and cumulative concentrations of Ca2+. The results suggest that the methanolic extract does not interact with classical opiate receptors and its effects, at least that produced on smooth muscle, may be due to a probable interference with calcium influx and/or calcium release from an intra-cellular store.
Tortoriello
J
J
División de Farmacología de Plantas Medicinales, Centro de Investigación Biomédica del Sur, IMSS, Morelos, México.
Aguilar-Santamaría
L
L
D000284:Administration, Oral; D000704:Analysis of Variance; D000818:Animals; D000930:Antidiarrheals / Q000494:pharmacology*; D002118:Calcium / Q000037:antagonists & inhibitors*; D003292:Convulsants / Q000008:administration & dosage / Q000633:toxicity; D004305:Dose-Response Relationship, Drug; D004357:Drug Synergism; D004558:Electric Stimulation; D005772:Gastrointestinal Transit / Q000187:drug effects; D006168:Guinea Pigs; D006993:Hypnotics and Sedatives / Q000008:administration & dosage / Q000494:pharmacology; D007082:Ileum / Q000187:drug effects / Q000378:metabolism; D008139:Loperamide / Q000494:pharmacology; D008297:Male; D008519:Medicine, Traditional; D000432:Methanol / Q000737:chemistry; D008800:Mexico; D051379:Mice; D008807:Mice, Inbred BALB C; D009119:Muscle Contraction / Q000187:drug effects; D009126:Muscle Relaxation / Q000187:drug effects; D009130:Muscle, Smooth / Q000187:drug effects*; D010424:Pentobarbital / Q000008:administration & dosage / Q000494:pharmacology; D010433:Pentylenetetrazole / Q000008:administration & dosage / Q000633:toxicity; D010936:Plant Extracts / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use*; D010946:Plants, Medicinal; D012640:Seizures / Q000188:drug therapy / Q000401:mortality / Q000517:prevention & control*; D013331:Strychnine / Q000008:administration & dosage / Q000633:toxicity
D000930:Antidiarrheals; D003292:Convulsants; D006993:Hypnotics and Sedatives; D010936:Plant Extracts; D008139:Loperamide; D013331:Strychnine; D010424:Pentobarbital; D002118:Calcium; D010433:Pentylenetetrazole; D000432:Methanol