Neonatal agonism of ER[beta] impairs male reproductive behavior and attractiveness
Publication Type: |
Journal Article |
Year of Publication: |
2011 |
Authors: |
Alana W. Sullivan, Peter Hamilton, Heather B. Patisaul |
Publication/Journal: |
Hormones and Behavior |
Keywords: |
dpn, endocrine disruptor, estrogen, estrogen receptor, genistein, masculinization, partner preference, sex behavior, soy, virility |
ISBN: |
0018-506X |
Abstract:
The organization of the developing male rodent brain is profoundly influenced by endogenous steroids, most notably estrogen. This process may be disrupted by estrogenic endocrine disrupting compounds (EDCs) resulting in altered sex behavior and the capacity to attract a mate in adulthood. To better understand the relative role each estrogen receptor (ER) subtype (ER[alpha] and ER[beta]) plays in mediating these effects, we exposed male Long Evans rats to estradiol benzoate (EB, 10 [mu]g), vehicle, or agonists specific for ER[beta] (DPN, 1 mg/kg) or ER[alpha] (PPT, 1 mg/kg) daily for the first four days of life, and then assessed adult male reproductive behavior and attractiveness via a partner preference paradigm. DPN had a greater adverse impact than PPT on reproductive behavior, suggesting a functional role for ER[beta] in the organization of these male-specific behaviors. Therefore the impact of neonatal ER[beta] agonism was further investigated by repeating the experiment using vehicle, EB and additional DPN doses (0.5 mg/kg, 1 mg/kg, and 2 mg/kg bw). Exposure to DPN suppressed male reproductive behavior and attractiveness in a dose dependent manner. Finally, males were exposed to EB or an environmentally relevant dose of genistein (GEN, 10 mg/kg), a naturally occurring xenoestrogen, which has a higher relative binding affinity for ER[beta] than ER[alpha]. Sexual performance was impaired by GEN but not attractiveness. In addition to suppressing reproductive behavior and attractiveness, EB exposure significantly lowered the testis to body weight ratio, and circulating testosterone levels. DPN and GEN exposure only impaired behavior, suggesting that disrupted androgen secretion does not underlie the impairment.