Actions of angiotensin II and dopamine in the medial preoptic area on prolactin secretion
Nenhuma Miniatura disponível
Data
2008-01-01
Autores
Leite, C. M.
Machado, G. J. R. [UNESP]
Dornelles, Rita Cassia Menegati [UNESP]
Franci, C. R.
Título da Revista
ISSN da Revista
Título de Volume
Editor
Acad Sciences Czech Republic, Inst Physiology
Resumo
Dopamine (DA) is known as a primary regulator of prolactin secretion (PRL) and angiotensin II (Ang II) has been recognized as one brain inhibitory factor of this secretion. In this work, estrogen-primed or unprimed ovariectornized rats were submitted to the microinjection of saline or Ang II after previous microinjection of saline or of da antagonist (haloperidol, sulpiride or SCH) both in the medial preoptic area (MPOA). Our study of these interactions has shown that 1) estrogen-induced PRL secretion is mediated by Ang II and da actions in the MPOA, i.e. very high plasma PRL would be prevented by inhibitory action of Ang II, while very low levels would be prevented in part by stimulatory action of da through D-2 receptors, 2) the inhibitory action of Ang II depends on estrogen and is mediated in part by inhibitory action of da through D, receptors and in other part by inhibition of stimulatory action of da through D2 receptors.
Descrição
Palavras-chave
prolactin, medial preoptic area, angiotensin II, dopaminergic antagonists, estrogen
Como citar
Physiological Research. Prague 4: Acad Sciences Czech Republic, Inst Physiology, v. 57, n. 1, p. 109-118, 2008.