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Prenatal Gonadal Influences on Mouse Sociosexual Behaviours

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Heterotypical Behaviour in Man and Animals

Abstract

A basic assumption in research on sexual differentiation has been that after differentiation of the gonads, testosterone (or its intracellular metabolites: 17ß-oestradiol and 5α-dihydrotestosterone) mediates the process of masculinization (the induction of species-specific masculine characteristics). Active defeminization (the loss of species-specific feminine characteristics) is proposed to occur in male rodents (but not primates, see e.g. Karsch & al., 1973) as a result of intracellular conversion of testosterone to oestradiol within specific areas of the brain. Examples of defeminization of specific traits in response to testosterone secretion by the male testes during early life in mice and rats are: the loss of the capacity to respond to elevated oestradiol by exhibiting a surge in LH or the sexually-receptive posture (lordosis) when mounted by a stud male (Gorski, 1979). A second hormone secreted by the foetal testes, Mullerian inhibiting hormone, is also reguired for active degeneration (defeminization) of the derivatives of the Mullerian ducts (fallopian tubes, uterus, and upper part of the vagina; Jost, 1972).

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Vom Saal, F.S. (1991). Prenatal Gonadal Influences on Mouse Sociosexual Behaviours. In: Haug, M., Brain, P.F., Aron, C. (eds) Heterotypical Behaviour in Man and Animals. Springer, Dordrecht. https://doi.org/10.1007/978-94-011-3078-3_3

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