The effects of PGE2 and PGF2 alpha on rhythmic contractions of sphincter of Oddi.
1. Spontaneous rhythmic activity observed in some of the guinea-pig sphincter of Oddi preparations was completely abolished by PGE2 (10(-8) M) but not altered by PGF2 alpha (10(-6) M). 2. Indomethacin (10(-5) M), a cyclooxygenase inhibitor, elicited long-lasting rhythmic contractions in 50% of the preparations tested, which did not show any spontaneous activity. PGE2 (10(-8) M) completely inhibited, however PGF2 alpha (10(-8)-10(-6) M) did not change the rhythmic contractions induced by indomethacin. 3. Both initial phasic contraction and the frequency and amplitude of peristaltic waves induced by ACh (10(-3) M) were increased by indomethacin (10(-5) M), decreased by PGE2 (10(-7) M) and not altered by PGF2 alpha (10(-7) M).
Göçer
F
F
Department of Pharmacology, Faculty of Medicine, Hacettepe University, Ankara, Turkey.
Yariş
E
E
Tuncer
M
M
D000109:Acetylcholine / Q000494:pharmacology; D000818:Animals; D015237:Dinoprost / Q000494:pharmacology*; D015232:Dinoprostone / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D005260:Female; D006168:Guinea Pigs; D007213:Indomethacin / Q000494:pharmacology; D008297:Male; D009119:Muscle Contraction; D009803:Sphincter of Oddi / Q000187:drug effects*
D015237:Dinoprost; D015232:Dinoprostone; D000109:Acetylcholine; D007213:Indomethacin