Open AccessLocalized actions of progesterone in hypothalamus involve oxytocin.
Author(s) -
Michaël Schumacher,
Héctor Coirini,
Maya Frankfurt,
Bruce S. McEwen
Publication year - 1989
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.86.17.6798
Subject(s) - oxytocin , medicine , endocrinology , estradiol benzoate , hypothalamus , ventromedial nucleus of the hypothalamus , oxytocin receptor , lordosis behavior , neuropeptide , estrogen , receptor , hormone , ovariectomized rat , biology , chemistry
Two ovarian hormones, estradiol and progesterone, which facilitate mating behavior in the female rat by acting on the ventromedial nuclei (VMN) of the hypothalamus, induce changes in oxytocin receptor binding in this brain region. Estradiol induced a 4-fold increase in the oxytocin receptor binding of the VMN and surrounding area and increased the number and immunostaining of oxytocin fibers in an area lateral to the ventral VMN. Progesterone, in estrogen-primed rats, caused the induced oxytocin receptors to spread over the area containing the oxytocin fibers. Infusion of oxytocin into the ventromedial hypothalamus increased the display of lordosis behavior only in females primed with both estradiol benzoate and progesterone. Thus, the sequential actions of two ovarian hormones bring a neuropeptide and its receptors into register and enable the neuropeptide to exert behavioral effects.