Changes in forebrain Na,K-ATPase activity and serum hormone levels during sexual behavior in male rats.
We have previously shown that Na,K-ATPase activity (the enzymatic machinery for the sodium pump) in brain areas such as the medial basal hypothalamus (MBH) and the preoptic-suprachiasmatic region (POSC) can be changed by experimental manipulations of gonadal function. We now report enzyme levels in brain regions as related to hormonal changes occurring during sexual behavior. Male rats were exposed to receptive females and decapitated immediately after displaying one of the following behavioral events: the start of copulatory activity, first ejaculation, and the beginning of a second copulatory series. A group of noncopulating animals were used as control. The variables measured included serum levels of LH, PRL and testosterone and Na,K-ATPase activity in MBH, POSC and parietal cerebral cortex (CC). A steady increase in enzyme activity in the POSC, but not the MBH or CC, was found in copulating animals. Serum LH levels changed in a similar fashion. A sharp increase in serum PRL levels, seemingly related to ejaculation, was also observed. These data are consistent with our previous findings on monoaminergic neurotransmission in brain regions related to male sexual behavior.
Oaknin
S
S
Department of Biochemistry, University of La Laguna, Tenerife, Spain.
Rodriguez del Castillo
A
A
Guerra
M
M
Battaner
E
E
Mas
M
M
D000818:Animals; D001921:Brain / Q000201:enzymology*; D002540:Cerebral Cortex / Q000201:enzymology; D007033:Hypothalamus, Middle / Q000201:enzymology; D007986:Luteinizing Hormone / Q000097:blood*; D008297:Male; D011301:Preoptic Area / Q000201:enzymology; D011388:Prolactin / Q000097:blood*; D051381:Rats; D011919:Rats, Inbred Strains; D012726:Sexual Behavior, Animal / Q000502:physiology*; D000254:Sodium-Potassium-Exchanging ATPase / Q000378:metabolism*; D013739:Testosterone / Q000097:blood*
D013739:Testosterone; D011388:Prolactin; D007986:Luteinizing Hormone; D000254:Sodium-Potassium-Exchanging ATPase