NMDA receptors in the medial zona incerta stimulate luteinizing hormone and prolactin release.

BREGONZIO C, MORENO GN, CABRERA RJ, DONOSO AO

CELLULAR AND MOLECULAR NEUROBIOLOGY.

Año: 2004 vol. 24 p. 331 - 331

0272-4340

p class="abstract">1. The aim of the present work is to demonstrate the interaction between the glutamatergic/NMDA and dopaminergic systems in the medial zona incerta on the control of luteinizing hormone and prolactin secretion and the influence of reproductive hormones. 2. Proestrus and ovariectomized rats were primed with estrogen and progesterone to induce high or low levels of luteinizing hormone and prolactin. 2-Amino-7-phosphonoheptanoic acid, an NMDA receptor antagonist, and dopamine were injected in the medial zona incerta. Blood samples were withdrawn every hour between 1,600 and 2,000 hours or 2,200 hours via intracardiac catheter from conscious rats. Additional groups of animals injected with the NMDA receptor antagonist were killed 1 or 4 h after injection. Dopamine and its metabolite 3,4-dihydroxyphenylacetic acid were measured in different hypothalamic regions. 3. 2-Amino-7-phosphonoheptanoic acid blocked the ovulatory luteinizing hormone surge in proestrus rats. 2-Amin