Stress Reducing Effects of Oxytocin in a Maternal Separation Paradigm

by O’Connell, Keely Jane

This study compared the effects of centrally and peripherally administered oxytocin (OT) on HPA axis activity and the presence of both stress-induced active and passive behaviors in female guinea pig pups (Cavia porcellus) after 180-min of isolation . In Experiment 1, one dose of oxytocin (10?g/.2ml) was injected subcutaneously into the periphery. Plasma cortisol levels were reduced after 180-min of isolation and two passive behaviors, eye-closure and crouch, were reduced as well with the administration of oxytocin. In Experiment 2, two different doses (10?g/.2ml and 20?g/.2ml) were injected into the periphery with no significant results. In Experiment 3 one dose of oxytocin (1?g/5?l) was infused centrally. Plasma cortisol levels were marginally reduced after 30-min of isolation. Both the active and passive behaviors were unchanged.