Perinatal Exposure to Low Levels of the Environmental Antiandrogen Vinclozolin Alters Sex-Differentiated Social Play and Sexual Behaviors
in the Rat Nathan K.W. Colbert, Nicole C. Pelletier, Joyce M. Cote, John B. Concannon, Nicole A. Jurdak, Sara B. Minott, and Vincent P. Markowski Maine Center for Toxicology and Environmental Health, University of Southern Maine, Portland, Maine, USA Abstract In this study we examined the effects of exposure to the antiandrogenic fungicide vinclozolin (Vz) on the development of two sex-differentiated behaviors that are organized by the perinatal actions of androgens. Pregnant Long-Evans rats were administered a daily oral dose of 0, 1.5, 3, 6, or 12 mg/kg Vz from the 14th day of gestation through postnatal day (PND) 3. The social play behavior of juvenile offspring was examined on PND22 and again on PND34 during play sessions with a same-sex littermate. After they reached adulthood, the male offspring were examined with the ex copula penile reflex procedure to assess erectile function. Vz did not produce any gross maternal or neonatal toxicity, nor did it reduce the anogenital distance in male pups. We observed no effects of Vz on play behavior on PND22. However, the 12-mg/kg Vz dose significantly increased play behavior in the male offspring on PND34 compared with controls. The most dramatic increases were seen with the nape contact and pounce behavior components of play. The Vz effect was more pronounced in male than in female offspring. As adults, male offspring showed a significant reduction of erections at all dose levels during the ex copula penile reflex tests. The 12-mg/kg dose was also associated with an increase in seminal emissions. These effects demonstrate that perinatal Vz disrupts the development of androgen-mediated behavioral functions at exposure levels that do not produce obvious structural changes or weight reductions in androgen-sensitive reproductive organs. Key words: antiandrogen, penile reflexes, prenatal exposure, rat, social play, vinclozolin. Environ Health Perspect 113:700-707 (2005) . doi:10.1289/ehp.7509 available via http://dx.doi.org/ [Online 16 March 2005] Address correspondence to V.P. Markowski, Department of Psychology, University of Southern Maine, 96 Falmouth St., 178 Science Building, Portland, ME 04104-9300 USA. Telephone: (207) 228-8174. Fax: (207) 228-8057. E-mail: markowski@usm.maine.edu We thank W.D. Thompson for his assistance with the statistical analyses and S.E. Frankel for his efforts proofreading the manuscript. This study was supported by a research grant from the Bioscience Research Institute of Southern Maine to V.P.M. The authors declare they have no competing financial interests. Received 18 August 2004 ; accepted 15 March 2005. Correction: The AGD data for control females were incorrect in Table 3 of the original manuscript published online, but they have been corrected here. An erratum was published in Environ Health Perspect 114:A342 (2006) . The full version of this article is available for free in HTML or PDF formats. |