Behavioral sensitization and voluntary ethanol drinking in alcohol-preferring AA rats exposed to different regimens of morphine treatment. Export

@article{citeulike:159103, abstract = {The purpose of the study was to investigate the effects of three different regimens of morphine treatment on subsequent voluntary ethanol drinking in alcohol-preferring AA (Alko Alcohol) rats. The rats were given morphine subcutaneously either intermittently on alternating days (15 x 10 mg/kg or 5 x 5-20 mg/kg in escalating doses) or subchronically on four consecutive days (3-20 mg/kg/d). Horizontal locomotor activity was monitored after challenges with additional morphine injections (3 mg/kg) ten days and six weeks after termination of the pretreatment to test if behavioral sensitization was induced by repeated morphine administration. Both intermittent pretreatments induced sensitized locomotor response after the first challenge, whereas subchronic injections did not. After the challenge the rats were given a free choice between tap water and 10\% (v/v) ethanol solution for four weeks. The rats pretreated and challenged with morphine did not differ significantly in the acquisition of ethanol drinking from the saline-treated controls. In contrast, ethanol drinking was impaired during the first week of ethanol access in the saline-treated rats given a single morphine injection. The second morphine challenge given after the ethanol-drinking phase did not reveal sensitization in any of the groups. The results suggest that pattern of morphine administration rather than the dose or number of exposures to the drug is the most important factor in induction of behavioral sensitization, and that exposure to ethanol may interfere with this process. They also support earlier findings showing that acute morphine may suppress voluntary ethanol drinking, but failed to provide clear evidence for behavioral sensitization to morphine contributing to predilection towards ethanol in AA rats.}, address = {Department of Mental Health and Alcohol Research, National Public Health Institute, POB 33, 00251 Helsinki, Finland.}, author = {Ojanen, S. P. and Hyyti\"{a}, P. and Kiianmaa, K.}, citeulike-article-id = {159103}, citeulike-linkout-0 = {http://dx.doi.org/10.1016/j.pbb.2004.11.012}, citeulike-linkout-1 = {http://view.ncbi.nlm.nih.gov/pubmed/15680175}, citeulike-linkout-2 = {http://www.hubmed.org/display.cgi?uids=15680175}, doi = {10.1016/j.pbb.2004.11.012}, issn = {0091-3057}, journal = {Pharmacol Biochem Behav}, keywords = {alcoholism, drugs, ethanol, morphine, rats}, month = {February}, number = {2}, pages = {221--228}, posted-at = {2005-04-12 13:35:54}, priority = {2}, title = {Behavioral sensitization and voluntary ethanol drinking in alcohol-preferring AA rats exposed to different regimens of morphine treatment.}, url = {http://dx.doi.org/10.1016/j.pbb.2004.11.012}, volume = {80}, year = {2005} }

TY - JOUR ID - citeulike:159103 L3 - citeulike-article-id:159103 N2 - The purpose of the study was to investigate the effects of three different regimens of morphine treatment on subsequent voluntary ethanol drinking in alcohol-preferring AA (Alko Alcohol) rats. The rats were given morphine subcutaneously either intermittently on alternating days (15 x 10 mg/kg or 5 x 5-20 mg/kg in escalating doses) or subchronically on four consecutive days (3-20 mg/kg/d). Horizontal locomotor activity was monitored after challenges with additional morphine injections (3 mg/kg) ten days and six weeks after termination of the pretreatment to test if behavioral sensitization was induced by repeated morphine administration. Both intermittent pretreatments induced sensitized locomotor response after the first challenge, whereas subchronic injections did not. After the challenge the rats were given a free choice between tap water and 10% (v/v) ethanol solution for four weeks. The rats pretreated and challenged with morphine did not differ significantly in the acquisition of ethanol drinking from the saline-treated controls. In contrast, ethanol drinking was impaired during the first week of ethanol access in the saline-treated rats given a single morphine injection. The second morphine challenge given after the ethanol-drinking phase did not reveal sensitization in any of the groups. The results suggest that pattern of morphine administration rather than the dose or number of exposures to the drug is the most important factor in induction of behavioral sensitization, and that exposure to ethanol may interfere with this process. They also support earlier findings showing that acute morphine may suppress voluntary ethanol drinking, but failed to provide clear evidence for behavioral sensitization to morphine contributing to predilection towards ethanol in AA rats. IS - 2 JF - Pharmacol Biochem Behav SN - 0091-3057 AD - Department of Mental Health and Alcohol Research, National Public Health Institute, POB 33, 00251 Helsinki, Finland. EP - 228 TI - Behavioral sensitization and voluntary ethanol drinking in alcohol-preferring AA rats exposed to different regimens of morphine treatment. VL - 80 SP - 221 KW - alcoholism KW - drugs KW - ethanol KW - morphine KW - rats AU - Ojanen, SP AU - Hyytiä, P AU - Kiianmaa, K PY - 2005/02// UR - http://dx.doi.org/10.1016/j.pbb.2004.11.012 ER -