Increased myometrial blood flow evoked by substance P.
Substance P (SP), a vasoactive neuropeptide, has recently been demonstrated in the female genital tract. In the present paper we have investigated the relationship between substance P (0, 0.065, 6.5, 650 pmol X min-1 X kg-1) administered by close intraarterial infusions, and myometrial blood flow (MBF). The MBF was measured by the 133Xe washout technique in ten non-pregnant, estrogen pretreated, female rabbits anaesthetized with sodium pentobarbitone. SP increased MBF in a dose-dependent fashion. This effect was not influenced by cholinergic, adrenergic or enkephalinergic blocking agents, indicating a direct effect of substance P on vascular smooth muscle. Substance P may therefore play a physiological role in the local nervous control of myometrial blood flow.
D000818:Animals; D001285:Atropine / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D005260:Female; D009215:Myometrium / Q000098:blood supply*; D009270:Naloxone / Q000494:pharmacology; D010643:Phenoxybenzamine / Q000494:pharmacology; D011433:Propranolol / Q000494:pharmacology; D011817:Rabbits; D012039:Regional Blood Flow / Q000187:drug effects; D013373:Substance P / Q000494:pharmacology*; D014599:Uterus / Q000098:blood supply*
D010643:Phenoxybenzamine; D013373:Substance P; D009270:Naloxone; D001285:Atropine; D011433:Propranolol