Enhaced D2-type receptor activity facilitates the development of conditioned same-sex partner preference in male rats

Pharmacol Biochem Behav. 2012 Aug;102(2):177-83. doi: 10.1016/j.pbb.2012.04.007. Epub 2012 Apr 28.


Animal models have shown that the neural bases of social attachment, sexual preference and pair bonds, depend on dopamine D2-type receptor and oxytocin activity. In addition, studies have demonstrated that cohabitation can shape partner preference via conditioning. Herein, we used rats to explore the development of learned same-sex partner preferences in adulthood as a result of cohabitation during enhanced D2 activity. Experimental Wistar males (N=20), received saline or the D2 agonist (quinpirole) and were allowed to cohabitate during 24 h, with a stimulus male partner that bore almond scent on the back as conditioned stimulus. This was repeated every 4 days, for a total of three trials. Four days later they were drug-free tested for partner preference between the scented male partner and a sexually receptive female. Sexual partner preference was analyzed by measuring frequency and latency for appetitive and consummatory sexual behaviors, as well as non-contact erections. Social preference was also analyzed by measuring the frequency and latency of visits, body contacts and time spent together. Results indicated that only quinpirole-treated males displayed sexual and social preference for the scented male over the sexually receptive female. They spent more time together, displayed more body contacts, more female-like proceptive behaviors, and more non-contact erections. Accordingly, conditioned males appeared to be more sexually aroused and motivated by the known male than by a receptive female. We discuss the implications of this animal model on the formation of learned homosexual partner preferences.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Conditioning, Classical*
  • Male
  • Rats
  • Rats, Wistar
  • Receptors, Dopamine D2 / physiology*
  • Sexual Behavior, Animal*


  • Receptors, Dopamine D2