Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0042755 (masculinization)
 2,562 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In the present study, we investigate the development of sex differences in the bed nucleus of the accessory olfactory tract (BAOT), a sexually dimorphic structure in which masculinization of male rats depends on the level of postnatal estradiol. Male and female Wistar rats were sacrificed postnatally when they were 1, 3, 7, 15, 45 and 60 days old, and stereological methods were used to estimate the volume and number of neurons in the BAOT of the subjects. With respect to volume, sex differences were established from P15. In relation to the number of neurons, the males acquire their adult morphological parameter by P15, while females show a decrease (P3), increase (from P3 to P15) and later decrease (from P15 to P45). Sex differences from P3 to P7 might be related to greater cell death in the BAOT of the females. These results support the hypothesis that both male and female rats reach their adult morphological pattern within this sexually dimorphic nucleus in an active manner.
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PMID:Development of sex differences in the bed nucleus of the accessory olfactory tract in the rat. 970 95

Estrogens play a significant role during mammalian brain development and are required for the masculinization of neuronal circuits involved in sex-specific behaviors and neuroendocrine functions. Cellular estrogen signalling is transmitted through nuclear estrogen receptors (ER) which are divided into two subforms: the ER-alpha as well as the recently cloned ER-beta have been demonstrated in the hypothalamus. In the present study, we have analyzed the sex-specific expression of ER-beta mRNA in the pre- and postnatal mouse hypothalamus/preoptic region (Hyp/POA) by semiquantitative RT-PCR. The ER-beta mRNA was detectable as early as embryonic day (E) 15 in the diencephalon of both sexes. In males, levels of mRNA expression in the Hyp/POA increased until birth and remained high throughout postnatal (P) development, whereas in females, such an increase was not observed. Significantly higher mRNA levels were detected in the male Hyp/POA from E17 until P15. Perinatal sex differences in ER-beta mRNA expression coincide with higher estrogen-forming rates in the male Hyp/POA. At present, no direct evidence is available which demonstrates that estrogen signalling through ER-beta is involved in brain development. However, data from our and other studies suggest a potential role for this signal transduction pathway for brain differentiation.
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PMID:Developmental sex differences in estrogen receptor-beta mRNA expression in the mouse hypothalamus/preoptic region. 977 37