Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: UMLS:C0042755 (
masculinization
)
2,562
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
The sex-dependent differentiation of monoamine oxidase (MAO) in the hypothalamus of 60-day-old, Charles River rats was found to involve only type A (
MAO-A
), and not type B (MAO-B) enzyme. In vivo inhibition of type A by clorgyline, and type B by (--)deprenyl, however, tended to decrease the specific activity of both types of MAO to a smaller extent in the female than in the male hypothalamus. When
masculinization
was prevented by neonatal administration of estradiol (E) to males, hypothalamic
MAO-A
and MAO-B activities increased in both control and MAO-inhibited rats. Androgenization of females, however, had little effect on the MAO activity. Whereas the effects of neonatal estrogenization were attributable neither to a direct influence of E nor to a sexual difference in the peripheral clearance of the MAO-inhibitor used, single, high doses of steroids to adult, but not to newborn rats, did acutely affect the kinetics of
MAO-A
. The activity of
MAO-A
was also decreased by high concentrations of E or TS in vitro. The imprinting for patterns of hypothalamic
MAO-A
and MAO-B in the two sexes results, probably, from genetic predetermination. Neonatal changes in the homeostasis of gonadal hormones may result in type-MAO nonspecific effects in adulthood, whereas the short-term effects of high concentrations of steroids may be selective for the A form.
...
PMID:Gonadal influences on the sexual differentiation of monoamine oxidase type A and B activities in the rat brain. 727 46
