Abstract # 143:

Scheduled for Friday, June 22, 2012 07:00 PM-09:00 PM: Session 22 (Gardenia) Poster Presentation


THE EFFECTS OF MU AND KAPPA OPIOID MANIPULATION IN THE MONOGAMOUS TITI MONKEY (CALLICEBUS CUPREUS)

B. J. Ragen1,2, N. Maninger2, S. P. Mendoza2 and K. L. Bales1,2
1University of California, Davis, Psychology Department, One Shields Ave, Davis, CA 95616, USA, 2California National Primate Research Center, Davis, CA
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     Mu opioid receptors (MOR) and kappa opioid receptors (KOR) are involved in social attachment and the stress response. The present study manipulated the opioid system in titi monkeys to test its involvement in the stress response under different social situations. In experiment 1, eight male titi monkeys underwent a 30-minute separation from their pair-mate followed by an injection of vehicle, morphine (0.25 mg/kg), naloxone (1.0 mg/kg), or the kappa agonist, U50,488, (0.01, 0.03, 0.1 mg/kg). Immediately after injection, they were reunited with their pair-mate for 30 minutes. Blood was sampled immediately prior to drug injection and after the 30-minute reunion. In experiment 2, eight male were given an injection of vehicle or the kappa antagonist, GNTI, (0.1, 0.5, 1.0 mg/kg). Twenty-four hours later they underwent a 60-minute social separation. Blood was sampled immediately prior to drug injection and social separation as well as after social separation. Blood samples were assayed for cortisol and vasopressin, two hormones representing the acute stress response, and analyzed with a generalized linear model. In Experiment 1, the increase in cortisol in response to naloxone was greater than all treatments (p<0.05) except for the high dose of U50,488. GNTI had no effect on cortisol (p>0.05). MOR blockade and KOR activation can increase plasma cortisol, however MOR activation and KOR blockade have no effect.