The effects of oxytocin and vasopressin on partner preferences in male and female prairie voles (Microtus ochrogaster).

Abstract

This study compared the effects of centrally administered oxytocin (OT) and arginine vasopressin (AVP) on partner preference formation and social contact in male and female prairie voles (Microtus ochrogaster). After 1 hr of cohabitation and pretreatment with either AVP or OT, both males and females exhibited increased social contact and significant preference for the familiar partner. After pretreatment with either an OT receptor antagonist (OTA) or an AVP (Via) receptor antagonist (AVPA), neither OT nor AVP induced a partner preference. In addition, treatment with OT+OTA or AVP+AVPA was associated with low levels of social contact in both sexes. Either AVP or OT is sufficient to facilitate social contact if either the OT or AVP receptor is available. However, the formation of partner preferences may require access to both AVP and OT receptors. Monogamous social systems are rare among mammals, occurring in less than 3% of mammalian species (Kleiman, 1977). Prairie voles (Microtus ochrogaster) exhibit several traits associated with monogamy, including high levels of social contact and the capacity to form pair bonds (Carter, DeVries, & Getz, 1995; Dewsbury, 1987; Dewsbury, Baumgardner, Evans, & Webster, 1980). In the laboratory, the selection of a familiar partner in preference to a stranger has been used as an index of pair bonding. Partner preferences can form during nonsexual cohabitation, and the onset of partner preferences is facilitated by mating (Williams, Catania, & Carter, 1992; Winslow, Hastings, Carter, Harbaugh, & Insel, 1993).