Adrenergic stimulation modifies prostaglandin synthesis by rat vas deferens.

The effects of norepinephrine on prostaglandin synthesis by isolated rat vas deferens were studied. The organ released prostaglandins (PGs) into the medium, especially PGE1 and also small amounts of PGE2 and PGF-like substances. Norepinephrine increased the amounts of PGE1 and PGE2-like material released into the medium without any change in those of PGF-like material. The effect of norepinephrine was inhibited by phenoxybenzamine and propranolol, but not by yohimbine. Inasmuch as mepacrine and corticosterone antagonized the response to norepinephrine on PG release the possible involvement of the adrenergic agonist on the activity of phospholipase A2 is suggested. It is concluded that norepinephrine elicits PGs-synthesis in rat vas deferens via an adrenoceptor stimulation. The adrenoceptor involved in this reaction, is probably postsynaptic (alpha 1).