Effects of maternal exposure to an aromatase inhibitor on sexual behaviour and neurochemical and endocrine aspects of adult male rat
Daniela C. C. Gerardin A B , Renata C. Piffer A , Patrícia C. Garcia A , Estefânia G. Moreira B and Oduvaldo C. M. Pereira A C
+ Author Affiliations
- Author Affiliations
A Department of Pharmacology, Institute of Biosciences, Sao Paulo State University—UNESP, 18618-000 Botucatu, Sao Paulo, Brazil.
B Department of Physiological Sciences, Londrina State University—UEL, 86051-990 Londrina, Parana, Brazil.
C Corresponding author. Email: pereira@ibb.unesp.br
Reproduction, Fertility and Development 20(5) 557-562 https://doi.org/10.1071/RD07213
Submitted: 29 November 2007 Accepted: 6 March 2008 Published: 28 April 2008
Abstract
The present study examined the effects of letrozole exposure during brain sexual differentiation on endocrine, behavioural and neurochemical parameters in male rat descendants. Pregnant female rats received 1 mg kg–1 day–1 letrozole or vehicle by oral gavage on gestational Days 21 and 22. Exposure to letrozole reduced anogenital distance in males on postnatal Day (PND) 22. At adulthood (PND 75), plasma testosterone levels and hypothalamic dopaminergic activity were increased, but sexual competence was impaired, because fewer successful sexual behaviours (mount, intromission and principally ejaculation) were observed. The impairment of reproductive function by prenatal exposure to an aromatase inhibitor reinforces the importance of adequate oestrogenic activity during perinatal sexual differentiation for complete masculinisation of the hypothalamus.
Additional keywords: hypothalamus, neurochemistry, sexual differentiation, striatum.
Acknowledgements
The authors are grateful to Eunice Oba for help with the determination of testosterone concentrations. This work constituted part of the doctoral thesis presented to the Universidade de São Paulo—USP by Daniela C. C. Gerardin and was supported by a fellowship from FAPESP (01/03458-0 and 04/08627-3).
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