Thyrotropin-releasing hormone affects the oxytocin, vasopressin and prolactin release in female rats during midlactation: relation to suckling.

摘要: The effect of thyrotropin-releasing hormone (TRH; 200 ng i.c.v.) on oxytocin (OT), vasopressin (AVP) and prolactin (PRL) release was estimated in female Wistar rats during midlactation. hypothalamo-neurohypophysial radioimmunoassayed OT AVP storage as well blood plasma level both neurohypophysial hormones PRL females suckled or not have been studied. I.c.v. administration TRH increased content the hypothalamus neurohypophysis females; however, did change. hypothalamic suckling. Simultaneously, inhibited into plasma. On contrary, concentration. raised concentration lactating but, at moment, females. i.c.v. injection just followed by a decrease level. probably acts central nervous system an inhibitory neuromodulating factor for release. Also, it cannot be excluded that TRH--otherwise known to enhance release--suppresses oxytocin-prolactin positive feedback mechanism when activated temporarily