The Role of beta-Adrenergic Receptor in the Seminal Vesicle Contraction / 대한비뇨기과학회지

ABSTRACT

PURPOSE: To investigate the role of beta-adrenergic receptors, and the relevance of NO-mediated & calcium channel-mediated signal transduction in seminal vesicle contractions. MATERIALS AND METHODS: Rabbit seminal vesicle strip preparations were applied to an organ bath system under standard condition. Smooth muscle contractions were induced by alpha and/or beta-adrenergic agonists (norepinephrine, phenylephrine, isoproterenol), and blocked by alpha (prazosin) and/or beta (propranolol)-blocker, an NO donor (sodium nitroprusside) and calcium channel blocker (verapamil). The contractility of the smooth muscle was measured by EC50. RESULTS: Norepinephrine, phenylephrine and isoproterenol produced a sudden increase in the contractions of the smooth muscle. The order of the adrenergic agonists in relation to increases in the contractility was norepinephrine>phenylephrine>isoproterenol. The contractions induced by norepinephrine and phenylephrine were partially blocked by prazosin, and those by isoproterenol were completely blocked by propranolol. The contraction induced by norepinephrine was partially blocked by sodium nitroprusside and verapamil, in dose dependant manners. CONCLUSIONS: Seminal vesicle contractions are mediated mostly by alpha-adrenergic receptors, and seem to be partly mediated by beta-adrenergic receptors. The contractility of seminal vesicle seems to be partly regulated by the NO-cGMP-cascade and calcium channel mediated signal transduction.