title: The effects of alpha- and beta-adrenergic stimulation on contractility and prostaglandin (prostaglandins E2 and F2 alpha and 6-keto-prostaglandin F1 alpha) production of pregnant human myometrial strips.
abstract: The effects of catecholamines and alpha- and beta-adrenergic agonists and antagonists on the spontaneous contractility of superfused pregnant human myometrial strips are reported. Prostaglandins (prostaglandins E2 and F2 alpha and 6-keto-prostaglandin F1 alpha) were analyzed in the effluent of the superfusion medium by specific radioimmunoassays. Both epinephrine and norepinephrine dose-dependently (10 ng/ml to 1 microgram/ml) stimulated the contractility of the myometrial strips and significantly increased the synthesis of all prostaglandins assayed. alpha-Adrenergic blockers inhibited the catecholamine-induced increase in contractility. This was associated with decreased prostaglandins F2 alpha and E2 concentrations and a further increase in 6-keto-prostaglandin F1 alpha levels. Exclusive beta-adrenergic stimulation with beta-mimetic drugs had the same effect. Conversely, epinephrine stimulation together with beta-blockers resulted in a further increase in the prostaglandins F2 alpha and E2 release of the myometrial strips. This effect was even more pronounced with specific alpha-adrenergic stimulant drugs. Our results demonstrate the interrelationship of alpha- and beta-adrenergic stimulation and the prostaglandin system. alpha-Adrenergic stimulation increases myometrial contractility and the synthesis of prostaglandins F2 alpha and E2. beta-Adrenergic stimulation reduces contractility by further enhancing 6-keto-prostaglandin F1 alpha production.
authors.forename: L
authors.initials: L
authors.lastname: Quaas
authors.forename: H P
authors.initials: HP
authors.lastname: Zahradnik
mesh_terms: D015121:6-Ketoprostaglandin F1 alpha / Q000096:biosynthesis; D000316:Adrenergic alpha-Agonists / Q000494:pharmacology*; D000317:Adrenergic alpha-Antagonists / Q000494:pharmacology*; D000318:Adrenergic beta-Agonists / Q000494:pharmacology*; D002395:Catecholamines / Q000494:pharmacology; D015237:Dinoprost; D015232:Dinoprostone; D005260:Female; D006801:Humans; D066298:In Vitro Techniques; D009215:Myometrium / Q000378:metabolism*; D011247:Pregnancy; D011453:Prostaglandins / Q000096:biosynthesis*; D011458:Prostaglandins E / Q000096:biosynthesis; D011460:Prostaglandins F / Q000096:biosynthesis; D014590:Uterine Contraction / Q000187:drug effects*
chemical_list: D000316:Adrenergic alpha-Agonists; D000317:Adrenergic alpha-Antagonists; D000318:Adrenergic beta-Agonists; D002395:Catecholamines; D011453:Prostaglandins; D011458:Prostaglandins E; D011460:Prostaglandins F; D015121:6-Ketoprostaglandin F1 alpha; D015237:Dinoprost; D015232:Dinoprostone