Social status in pairs of male squirrel monkeys determines the behavioral response to central oxytocin administration

Abstract

Oxytocin, when administered centrally, has been associated with the modulation of various social initiatives including maternal and sexual behaviors. The nature of these effects depends on gonadal hormone status. In the present experiments, we investigated the effects of centrally administered oxytocin on the behavior of pair-housed male squirrel monkeys during interactions with a familiar female monkey. Pairs of male squirrel monkeys established reliable and persistent dominance relationships with dominant males showing increased sexual and aggressive behavior as well as higher plasma concentrations of testosterone. Oxytocin (0.1, 1.0 micrograms) increased the sexual and aggressive behavior of dominant monkeys without affecting these measures in the subordinate monkeys. In contrast to these effects in the dominant monkeys, oxytocin increased associative and marking behaviors only in subordinate monkeys. Central administration of the oxytocin receptor antagonis d(CH2)5 [Tyr(Me)2, Thr4,Tyr-NH2(9)] OVT (OTA; 0.05 microgram) had no intrinsic effect on behavior but blocked the effects of exogenous oxytocin. To investigate further the specificity of oxytocin's effects on social behavior, we administered the structurally related peptide arginine vasopressin under identical conditions. Vasopressin (0.5, 5.0 micrograms) decreased social behaviors and increased motor activity in both dominant and subordinate monkeys. Previous studies in rodents have demonstrated that oxytocin receptors are induced by gonadal steroids in a regionally specific fashion. The status-related behavioral effects of oxytocin in the squirrel monkey may reflect differences in brain oxytocin receptor density associated with the higher concentrations of testosterone in the dominant animal. Alternatively, the status-related effects may depend on the conditioned behavioral differences associated with social organization.

Neural circuits underlying crying and cry responding in mammals

“…A review of some of the evidence for neurochemical control of vocalizations in anxiety-provoking circumstances has been presented by Newman [72]. In addition, the neuropeptides vasopressin (AVP) and oxytocin (OT) have attracted a lot of interest, due to the evidence that they are involved in regulating social attachment behavior in rodents and non-human primates [39,41,42,49,70,92,120,121].…”

From Galactorrhea to Osteopenia: Rethinking Serotonin–Prolactin Interactions

“…The magnocellular OT and AVP cells project to the posterior lobe of the pituitary, while the parvocellular division projects to the AP via the median eminence. OT, which is found only in mammals, is associated with reproductive and maternal behaviors, and is also implicated in a variety of social behaviors (Hughes et al, 1987;Insel, 1992;Winslow and Insel, 1991). It is specifically involved in the initiation of parturition and milk ejection, and is itself a stimulator of PRL secretion (see below) (Samson et al, 1986).…”

Oxytocin Infusion Reduces Repetitive Behaviors in Adults with Autistic and Asperger's Disorders

“…Peripheral and central oxytocin administration also inhibits extinction and this promotes perseverative behaviors (de Wied et al, 1993). Central administration of vasopressin results in increased aggression and self-directed behaviors in rodents (Brown and King, 1984;Winslow and Insel, 1991), which Insel et al (1999) has suggested may be related to the self-injurious behavior, often stereotyped, observed in children with autism. Although analogies between animal and human behavior must be viewed with caution, these studies suggest that oxytocin may play a role in repetitive behaviors, a core feature of autism.…”