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. 1986 Oct;83(19):7527–7531. doi: 10.1073/pnas.83.19.7527

Sexual dimorphism in human and canine spinal cord: role of early androgen.

N G Forger, S M Breedlove
PMCID: PMC386752  PMID: 3463982

Abstract

Onuf's nucleus, located in the sacral spinal cord of dogs, cats, and primates, innervates perineal muscles involved in copulatory behavior. A sexual dimorphism in Onuf's nucleus was found in humans and dogs: males have significantly more motoneurons in this nucleus than do females. Prenatal androgen treatment of female dogs eliminated the dimorphism. In the homologous nucleus in rats, a similar effect of androgen has been shown to involve sparing of motoneurons from cell death. These results establish a morphological sex difference in a human central nervous system region of known function; well-studied animal models suggest explanations of the development of this dimorphism.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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