The effect of prostaglandins and other vasoactive substances on uterine blood flow and myometrial activity.
The effects of prostaglandins (PG's), bradykinin, and adenosine on uterine blood flow (UBF) and intrauterine pressure (IUP) were investigated in conscious oophorectomized ewes. PGE1 and adenosine increased UBF to levels comparable to those induced by estradiol-17beta, whereas PGE2 and PGA1 achieved only 20 and 36 per cent of peak estradiol-induced levels, respectively. PGE1, PGE2, and adenosine all caused transient increases in IUP while PGA1 had no effect on myometrial activity. Bradykinin increased UBF to 60 per cent of peak estradiol-induced levels, with concomitant increases in IUP tonus. PGE2 and PGF2alpha decreased peak estrogen-induced UBF by 50 and 70 per cent, respectively, while inducing related increases in IUP. When compared with oxytocin, the effects of PGE2 at high flow appeared to be mediated only my myometrial activity, whereas PGF2alpha apparently caused vasoconstriction as well. These findings support the concept that PGE1 could play a role in mediating estrogen-induced uterine vasodilatation.
D000241:Adenosine / Q000494:pharmacology*; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D001920:Bradykinin / Q000494:pharmacology*; D002369:Castration; D004958:Estradiol; D005260:Female; D009129:Muscle Tonus / Q000187:drug effects; D009215:Myometrium / Q000187:drug effects*; D010121:Oxytocin / Q000494:pharmacology; D011312:Pressure; D011453:Prostaglandins / Q000494:pharmacology*; D011454:Prostaglandins A / Q000494:pharmacology; D011458:Prostaglandins E / Q000494:pharmacology; D011460:Prostaglandins F / Q000494:pharmacology; D012039:Regional Blood Flow / Q000187:drug effects; D012756:Sheep; D014599:Uterus / Q000098:blood supply / Q000187:drug effects* / Q000502:physiology*; D014661:Vasoconstriction / Q000187:drug effects; D014666:Vasomotor System / Q000187:drug effects
D011453:Prostaglandins; D011454:Prostaglandins A; D011458:Prostaglandins E; D011460:Prostaglandins F; D004958:Estradiol; D010121:Oxytocin; D000241:Adenosine; D001920:Bradykinin