The Role of Oxytocin Receptors in Male Rat Motivational and Consummatory Sexual Behaviors
Past research indicates that oxytocin is important for male rat consummatory sexual behaviors, but the role of oxytocin in motivational aspects of sexual behavior have yet to be determined. Sexually experienced Long-Evans male rats were administered either an oxytocin receptor antagonist (L368.899 hydrochloride; 1 mg/kg) or vehicle control into the intraperitoneal cavity forty-minutes prior to placement into the center chamber of a three-chambered arena that was designed to assess sexual motivation. During the 20-minute test, a sexually experienced stimulus male rat and a sexually receptive ovariectomized stimulus female rat (treated with estradiol benzoate and progesterone) were separately placed into one of two incentive animal cages attached to the outside larger end chambers. Physical contact between test and stimulus rats was prevented by perforated dividers that separated the incentive cages from the larger end chambers. Sexual motivation was operationalized by the amount of time test male rats spent in the vicinity of a sexually receptive female. Immediately following the sexual motivation test, test male rats were placed with a sexually receptive ovariectomized female rat in order to examine consummatory sexual behavior. Results indicated that both groups of rats spent more time with the female relative to chance, but treatment with an oxytocin receptor antagonist decreased the time spent with female, indicating a reduction in sexual motivation. These results have important implications for understanding the biological basis of sexual behavior in both rats and humans.
Franklin and Marshall College Archives, Undergraduate Honors Thesis 2016
- F&M Theses Collection