Authors: Andre DerAvakian Matthew J Will Sondra T Bland Terrence Deak Kien T Nguyen Megan J Schmid Robert L Spencer Linda R Watkins Steven F Maier
Publish Date: 2004/11/17
Volume: 179, Issue: 2, Pages: 409-417
Abstract
Stress and one of the physiological components of most stress responses glucocorticoid hormones CORT are known to influence the rewarding effects of a number of drugs of abuse We have previously shown that an acute uncontrollable stressor inescapable shock IS potentiates the rewarding effects of morphine using conditioned place preference CPPFirst the CORT response to 30 mg/kg morphine was measured in male Sprague–Dawley rats 24 h following exposure to IS Second we determined the effect of adrenalectomy ADX on the ISpotentiated CPP to morphine Finally we used the temporary CORT synthesis inhibitors metyrapone and aminoglutethimide to determine the necessity of CORT rises during either IS or morphine administration on the potentiated CPP responsePrior IS significantly potentiated the CORT response to morphine ADX significantly blocked the potentiated CPP to morphine produced by previous IS However CORT inhibition during IS had no effect on the IS potentiation of morphine CPP whereas inhibition during morphine administration completely blocked this potentiationThe results indicate that the CORT response to morphine is enhanced in rats that were previously exposed to an uncontrollable stressor and that this response to the drug not the stressor is necessary for the stressenhanced potentiation of morphine CPP
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