Protracted milk-ejecting effect of some oxytocin analogues in rats.

Protracted effect of [2-0-methyltyrosine]-deamino-1-carba-oxytocin, [2-0-methyltyrosine]-oxytocin and its dimeric form was studied on the mammary gland of lactating rat in vivo. Biphasic course of biological response found for monomers and slow onset of response observed for dimer led to the assumption that the substances behaved like hormonogens.