The possible role of endothelin(s) in cyclosporine A preparations--induced contraction of guinea pig isolated gallbladder strips.
1. In guinea-pig isolated gallbladder strips, both cyclosporine A (CyA) preparations and their vehicles (10(-7) M-4 x 10(-5) M) caused stable, long-lasting and concentration-dependent contractions. 2. Some gallbladder strips showed spontaneous rhythmic activity. CyA and its vehicles increased this rhythmic activity. Furthermore, they elicited rhythmic activity in the strips that did not show any spontaneous rhythmic activity. 3. Bosentan (10(-5) M) and verapamil (10(-5) M) partly but significantly inhibited the contractions due to CyA preparations and their vehicles except the effect of verapamil on Labrafil-induced contraction. 4. Neither parenteral and oral solutions of CyA nor their vehicles caused any contractile response on the sphincter of Oddi preparations.
Erdem
S R
SR
Department of Pharmacology, Faculty of Medicine, Hacettepe University, Ankara, Turkey.
Yaşar
U
U
Tuncer
M
M
D000818:Animals; D000077300:Bosentan; D016572:Cyclosporine / Q000494:pharmacology*; D016232:Endothelins / Q000037:antagonists & inhibitors / Q000096:biosynthesis / Q000502:physiology*; D005260:Female; D005704:Gallbladder / Q000187:drug effects*; D006168:Guinea Pigs; D066298:In Vitro Techniques; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects; D009130:Muscle, Smooth / Q000187:drug effects*; D014677:Pharmaceutical Vehicles / Q000494:pharmacology; D009803:Sphincter of Oddi / Q000187:drug effects*; D013449:Sulfonamides / Q000494:pharmacology; D014700:Verapamil / Q000494:pharmacology
D016232:Endothelins; D014677:Pharmaceutical Vehicles; D013449:Sulfonamides; D016572:Cyclosporine; D014700:Verapamil; D000077300:Bosentan