The influence of testosterone in the brain of the male rat on levels of serotonin (5-HT) and hydroxyindole-acetic acid (5-HIAA).
There were two groups of rats: one was injected with testosterone propionate (10 mg/kg) every 7 days starting from weaning (23 days old); the other group had gonadectomy on the same day. The levels of 5-HT and 5-HIAA were measured by spectrofluorometry. The concentrations of 5-HT in the diencephalon of the testosterone propionate injected rats decreased significantly at 45 days, tending to become reestablished at 60 days; the rest of the brain followed the same pattern, but was less pronounced. The concentrations of 5-HIAA in the diencephalon and the rest of the brain decrease throughout postnatal development, although the differences are not significant. The castrated rats showed a marked increase at 45 days and later decreased at 60 days without recovering their initial values, in both brain areas. 5-HIAA concentrations were similar to those found in the injected animals. These facts can have various interpretations: early modifications in the brain, feed-back regulation mechanisms at the level of the hypothalamus, decrease in the release of the amine or reduction of its catabolism.
Martinez-Conde
E
E
Leret
M L
ML
Diaz
S
S
D000818:Animals; D001921:Brain / Q000187:drug effects* / Q000378:metabolism; D002369:Castration; D006897:Hydroxyindoleacetic Acid / Q000378:metabolism*; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D012701:Serotonin / Q000378:metabolism*; D013739:Testosterone / Q000494:pharmacology*
D012701:Serotonin; D013739:Testosterone; D006897:Hydroxyindoleacetic Acid