Dantrolene sodium: stimulatory and depressant effects on the contractility of guinea-pig uterus in vitro.
The effects of dantrolene sodium on the spontaneous and oxytocin-induced contraction of guinea-pig uterus were studied in vitro. Dantrolene reversibly increased the spontaneous contraction frequency of guinea-pig uterus. The effect was not dose-related and was not antagonized by atropine, methysergide or indomethacin. Dantrolene dose dependently and reversibly reduced the contractile responses of guinea-pig uterus to oxytocin. The varying effects of dantrolene on the uterus probably involve inhibition of calcium movement at more than one site of the muscle.
D000818:Animals; D001285:Atropine / Q000494:pharmacology; D002118:Calcium / Q000378:metabolism; D003620:Dantrolene / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D005260:Female; D006168:Guinea Pigs; D007213:Indomethacin / Q000494:pharmacology; D008784:Methysergide / Q000494:pharmacology*; D009215:Myometrium / Q000378:metabolism; D010121:Oxytocin / Q000494:pharmacology; D014590:Uterine Contraction / Q000187:drug effects*
D010121:Oxytocin; D001285:Atropine; D003620:Dantrolene; D002118:Calcium; D007213:Indomethacin; D008784:Methysergide