Effect of a novel benzamide, YM-09151-2, on rat serum prolactin levels.
YM-09151-2(cis-N-(1-benzyl-2-methylpyrrolidin-3-yl) -5-chloro-2-methoxy-4-methylaminobenzamide) is a new benzamide which has been reported to be an antagonist of dopamine (DA) at D1-type DA receptors. In the present study, we have examined the extent of the interaction of YM-09151-2 with D2-type DA receptors in the anterior pituitary gland of the rat. YM-09151-2 was found to be a potent antagonist of these receptors as extremely low doses of this compound produced a marked, dose-dependent elevation of serum prolactin concentrations. This benzamide was also a potent blocker of DA-induced inhibition of prolactin release in vitro and was very effective in displacing 3H-spiperone from bovine pituitary membranes: IC50, 1.04nM. These results are consistent with recent evidence that YM-09151-2 is also a potent antagonist of the D2-type receptors in the intermediate lobe of the rat pituitary gland.
D000818:Animals; D001549:Benzamides / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D008297:Male; D010903:Pituitary Gland, Anterior / Q000187:drug effects* / Q000378:metabolism; D011388:Prolactin / Q000097:blood*; D051381:Rats; D011919:Rats, Inbred Strains; D011954:Receptors, Dopamine / Q000187:drug effects* / Q000378:metabolism; D013134:Spiperone / Q000378:metabolism; D013997:Time Factors
D001549:Benzamides; D011954:Receptors, Dopamine; D013134:Spiperone; D011388:Prolactin; C030265:nemonapride