Transforming growth factor-alpha gene expression in the hypothalamus is developmentally regulated and linked to sexual maturation.

Division of Neuroscience, Oregon Regional Primate Research Center, Beaverton 97006.
Neuron (Impact Factor: 15.77). 11/1992; 9(4):657-70. DOI: 10.1016/0896-6273(92)90029-D
Source: PubMed

ABSTRACT Hypothalamic injury causes female sexual precocity by activating luteinizing hormone-releasing hormone (LHRH) neurons, which control sexual development. Transforming growth factor-alpha (TGF-alpha) has been implicated in this process, but its involvement in normal sexual maturation is unknown. The present study addresses this issue. TGF-alpha mRNA and protein were found mostly in astroglia, in regions of the hypothalamus concerned with LHRH control. Hypothalamic TGF-alpha mRNA levels increased at times when secretion of pituitary gonadotropins--an LHRH-dependent event--was elevated, particularly at the time of puberty. Gonadal steroids involved in the control of LHRH secretion increased TGF-alpha mRNA levels. Blockade of TGF-alpha action in the median eminence, a site of glial-LHRH nerve terminal association, delayed puberty. These results suggest that TGF-alpha of glial origin is a component of the developmental program by which the brain controls mammalian sexual maturation.

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