Enhancement of estrogen receptor gene expression in the mediobasal hypothalamus during anestrus in the beagle bitch.
Estrogen receptor mRNA (ER mRNA) levels were measured in the mediobasal hypothalamus (MBH) of beagle bitches at different stages of the estrous cycle, and compared with levels in ovariectomized (OVX) estrogen-treated bitches. In cyclic bitches, the level of hypothalamic ER mRNA increased during the progression of anestrus and declined thereafter. Hypothalamic ER mRNA and plasma luteinizing hormone (LH) levels during anestrus and proestrus were positively correlated (r = 0.94, P < 0.001). In OVX bitches, levels of hypothalamic ER mRNA were low, and increased significantly after treatment with a low dose of estradiol benzoate. These results suggest that, during the course of anestrus in the bitch, hypothalamic ER mRNA expression increases, and may be up-regulated by estradiol.
Tani
H
H
Department of Animal Reproduction, College of Agriculture, Osaka, Prefecture University, Japan.
Inaba
T
T
Matsuyama
S
S
Takamori
Y
Y
Torii
R
R
Takano
H
H
Tamada
H
H
Sawada
T
T
D000818:Animals; D001483:Base Sequence; D003001:Cloning, Molecular; D004285:Dogs; D004958:Estradiol / Q000494:pharmacology; D004971:Estrus / Q000502:physiology*; D005260:Female; D015870:Gene Expression / Q000187:drug effects / Q000502:physiology; D006801:Humans; D007033:Hypothalamus, Middle / Q000737:chemistry* / Q000502:physiology; D007986:Luteinizing Hormone / Q000235:genetics; D008969:Molecular Sequence Data; D010052:Ovariectomy; D016133:Polymerase Chain Reaction; D011374:Progesterone / Q000235:genetics; D012333:RNA, Messenger / Q000378:metabolism; D011863:Radioimmunoassay; D051381:Rats; D011960:Receptors, Estrogen / Q000235:genetics*; D014404:Tubulin / Q000235:genetics
D012333:RNA, Messenger; D011960:Receptors, Estrogen; D014404:Tubulin; D011374:Progesterone; D004958:Estradiol; D007986:Luteinizing Hormone