Stimulation Of Medial Preoptic Area Research Articles

Effects of electrochemical stimulation of medial preoptic area on prolactin and luteinizing hormone release in old female rats.

Serum prolactin and LH levels in old constant estrous rats were higher than in old pseudopregnant rats. Electrochemical stimulation of the medial preoptic area in old constant estrous rats resulted in significant increases in serum concentration of prolactin and LH, and subsequent ovulation. Old pseudopregnant rats showed only a small increase in serum prolactin, no increase in serum LH and no ovulation. The high circulating levels of estrogen in old constant estrous rats, and the relative lack of estrogen and the presence of progesterone in the old pseudopregnant rats, may account for the differences observed in response of the medial preoptic area to electrochemical stimulation.