"Copulatory memory": A novel model for the study of recognition in the adult male rat

The experiments reported herein examine a form of recognition that occurs in rats within the context of mating behavior. Sexually-naive, adult, male rats are capable of recognizing familiar females with which they have previously interacted. This so-called "copulatory memory" model attempts to define a functional system which is characterized by changes in adult male rats' behavioral displays. These changes are a function of the male's recognition of a familiar female conspecific. In these studies, the male's recognition of the familiar female is associated with the exhibition of rapid mounting of the female and decreased female-directed olfactory investigation. The recognition of the familiar conspecific is dependent on the amount of time the male is physically exposed to the female and the odor of cues found in her urine. The duration of the "memory" is approximately three hours, though there is a great deal of individual variation. The rat's capacity to recognize the female is affected by his age, previous sexual experience, hormone status, and the activity of the peptide, arginine vasopressin. Specifically, the aged male rat which has had little or no previous sexual experience will show deficits in his capacity to recognize a familiar female. In addition, castration and the administration of arginine vasopressin antagonists disrupt the male's ability to recognize a familiar conspecific. This recognition is modulated by processing in the vomeronasal organ and the accessory olfactory bulb (AOB) as evidenced by the activation of the immediate early gene c-fos in the granular cell layer of the male's AOB following interaction with a receptive female.U of I OnlyETDs are only available to UIUC Users without author permissio