Changes in estrogen-alpha receptor immunoreactivity during the estrous cycle in lactating dairy cattle.
Estradiol is one of the most important hormones in the regulation of estrous behavior, which is at a very low level of expression in the modern dairy cow. In the present study the neuroanatomical distribution of estrogen receptors of the alpha-subtype (ER-alpha) in the bovine hypothalamic area is determined with immunocytochemical methods, at various stages of the estrous cycle. During the luteal phase of the cycle, ER-alpha immunoreactive cells were found in most of the nuclei that are known to express ER-alpha immunoreactivity in other species, like the Bed nucleus of the Stria terminalis, Medial preoptic area, Ventromedial hypothalamus and Arcuate nucleus. During estrus and metestrus, however, no ER-alpha immunoreactive cells could be detected in those areas, except for a few in the caudal Arcuate nucleus. The results from the present study indicate that there is a coherent regulation and timing of physiological and behavioral events around ovulation, in which estradiol and its receptor play a key role.
van Eerdenburg
F J
FJ
Department Farm Animal Health, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 7, 3584 CL, The, Utrecht, Netherlands. f.j.c.m.vaneerdenburg@vet.uu.nl
Daemen
I A
IA
van der Beek
E M
EM
van Leeuwen
F W
FW
D000818:Animals; D001111:Arcuate Nucleus of Hypothalamus / Q000502:physiology; D002417:Cattle; D047628:Estrogen Receptor alpha; D004971:Estrus / Q000502:physiology*; D005260:Female; D007031:Hypothalamus / Q000166:cytology / Q000502:physiology*; D007150:Immunohistochemistry; D007774:Lactation / Q000502:physiology*; D009474:Neurons / Q000166:cytology / Q000502:physiology; D011301:Preoptic Area / Q000502:physiology; D011960:Receptors, Estrogen / Q000032:analysis / Q000502:physiology*; D014697:Ventromedial Hypothalamic Nucleus / Q000502:physiology
D047628:Estrogen Receptor alpha; D011960:Receptors, Estrogen