Effects of uterine stimulant drugs on prostacyclin production by the pregnant rat myometrium. I. Oxytocin, bradykinin and PGF2 alpha.
The release of prostacyclin from chopped myometrial fractions of 18-20 day pregnant rats was assayed by inhibition of ADP-induced aggregation of citrated rabbit platelet-rich plasma. Preincubation of myometrial tissue with oxytocin 10 mU/ml increased prostacyclin generation from 2.25 +/- 0.48 (control) to 3.75 +/- 0.73 ng/mg over 15 minutes. Bradykinin 20 microgram/ml also caused a significant increase in myometrial prostacyclin output from 2.26 +/- 0.19 to 4.26 +/- 0.64 ng/mg. PGF2 alpha 1 microgram/ml did not increase prostacyclin release significantly. Pretreatment of myometrial tissue with the phospholipase inhibitor mepacrine significantly reduced the peptide-stimulated release of prostacyclin. The results suggest that prostacyclin production may play an important role in modulating the actions of oxytocin and bradykinin in the pregnant rat myometrium.
D000244:Adenosine Diphosphate / Q000494:pharmacology; D000818:Animals; D001920:Bradykinin / Q000494:pharmacology*; D011464:Epoprostenol / Q000096:biosynthesis*; D005260:Female; D009215:Myometrium / Q000187:drug effects / Q000378:metabolism*; D009391:Nephelometry and Turbidimetry; D010121:Oxytocin / Q000494:pharmacology*; D010974:Platelet Aggregation / Q000187:drug effects; D011247:Pregnancy; D011453:Prostaglandins / Q000096:biosynthesis*; D011460:Prostaglandins F / Q000494:pharmacology*; D051381:Rats; D014599:Uterus / Q000378:metabolism*
D011453:Prostaglandins; D011460:Prostaglandins F; D010121:Oxytocin; D000244:Adenosine Diphosphate; D011464:Epoprostenol; D001920:Bradykinin