Perinatal Exposure to Low Levels of the Environmental Antiandrogen Vinclozolin Alters Sex-Differentiated Social Play and Sexual Behaviors in the Rat

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

The Effects of Diet Induced Obesity and Metabolic Irregularities on Hippocampal-Based Cognition and Neuroplasticity in Young Female and Male Rat

Recent research has associated obesity with cognitive impairments and alterations in brain-derived neurotrophic factor (BDNF), with the majority of studies examining this in older adult or aging animals. To expand upon these efforts, two experiments were performed to examine the effects of diet-induced obesity (DIO) on spatial performance and hippocampal BDNF expression in young adult female and male rats. To expand upon these efforts, we examined these effects over dietary interventions of differing durations. To investigate these issues rats (female rats in Experiment 1 and male rats in Experiment 2) were assigned to either a standard chow condition or a DIO condition and remained on these diets for 4-, 8- or 12-weeks. Compared to their chow-fed counterparts, female DIO rats consumed significantly more average weekly calories, weighed significantly more, and exhibited significant alterations in glucose metabolism. However, these obesity-related physiological changes were not associated with concurrent impairments in spatial ability as measured using the Morris water maze, and only the 4-week DIO dietary intervention demonstrated a difference in hippocampal BDNF mRNA expression. Compared to their chow-fed counterparts, male DIO rats consumed significantly more average weekly calories than their chow-fed counterparts, weighed significantly more, and exhibited significant alterations in glucose metabolism. However, obesity-related physiological alterations were not associated with concurrent impairments in spatial ability or differences in BDNF mRNA expression, with the exception of the 12-week DIO animals performing significantly better than their chow-fed counterparts during the reversal probe trial on the final day of training. These findings were unexpected and will be discussed further later in the thesis

Tissue Disposition and Developmental Neurotoxicity of Inorganic Arsenic Following Gestational Exposure to Contaminated Drinking Water

Abstracts, Behavioral Toxicology Society, 24th Annual Meeting

Perinatal Exposure to Low Levels of the Environmental Antiandrogen Vinclozolin Alters Sex-Differentiated Social Play and Sexual Behaviors in the Rat

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 androgensensitive reproductive organs

Perinatal Exposure to Low Levels of the Environmental Antiandrogen Vinclozolin Alters Sex-Differentiated Social Play and Sexual Behaviors in the Rat-2

<p><b>Copyright information:</b></p><p>Taken from "Perinatal Exposure to Low Levels of the Environmental Antiandrogen Vinclozolin Alters Sex-Differentiated Social Play and Sexual Behaviors in the Rat"</p><p>Environmental Health Perspectives 2005;113(6):700-707.</p><p>Published online 16 Mar 2005</p><p>PMCID:PMC1257594.</p><p>This is an Open Access article: verbatim copying and redistribution of this article are permitted in all media for any purpose, provided this notice is preserved along with the article's original DOI.</p

Perinatal Exposure to Low Levels of the Environmental Antiandrogen Vinclozolin Alters Sex-Differentiated Social Play and Sexual Behaviors in the Rat-7

<p><b>Copyright information:</b></p><p>Taken from "Perinatal Exposure to Low Levels of the Environmental Antiandrogen Vinclozolin Alters Sex-Differentiated Social Play and Sexual Behaviors in the Rat"</p><p>Environmental Health Perspectives 2005;113(6):700-707.</p><p>Published online 16 Mar 2005</p><p>PMCID:PMC1257594.</p><p>This is an Open Access article: verbatim copying and redistribution of this article are permitted in all media for any purpose, provided this notice is preserved along with the article's original DOI.</p

Perinatal Exposure to Low Levels of the Environmental Antiandrogen Vinclozolin Alters Sex-Differentiated Social Play and Sexual Behaviors in the Rat-3

<p><b>Copyright information:</b></p><p>Taken from "Perinatal Exposure to Low Levels of the Environmental Antiandrogen Vinclozolin Alters Sex-Differentiated Social Play and Sexual Behaviors in the Rat"</p><p>Environmental Health Perspectives 2005;113(6):700-707.</p><p>Published online 16 Mar 2005</p><p>PMCID:PMC1257594.</p><p>This is an Open Access article: verbatim copying and redistribution of this article are permitted in all media for any purpose, provided this notice is preserved along with the article's original DOI.</p

Perinatal Exposure to Low Levels of the Environmental Antiandrogen Vinclozolin Alters Sex-Differentiated Social Play and Sexual Behaviors in the Rat-5

<p><b>Copyright information:</b></p><p>Taken from "Perinatal Exposure to Low Levels of the Environmental Antiandrogen Vinclozolin Alters Sex-Differentiated Social Play and Sexual Behaviors in the Rat"</p><p>Environmental Health Perspectives 2005;113(6):700-707.</p><p>Published online 16 Mar 2005</p><p>PMCID:PMC1257594.</p><p>This is an Open Access article: verbatim copying and redistribution of this article are permitted in all media for any purpose, provided this notice is preserved along with the article's original DOI.</p