Abstract
Adult female Sprague-Dawley rats were prepared with chronically implanted cortical and temporal muscle electrodes and i.v. cannulae. Morphine injections of 10 mg/kg were given i.p. to naive rats and to post-addict rats at successive intervals following morphine withdrawal. These intervals extended in a few cases up to one year. In the naive rat, high voltage EEG slow bursts associated with stuporous behavior appeared almost immediately after injection and prevailed for 60–90 min. This phase was followed by continuous EEG and behavioral arousal for another period of 60–90 min, after which sleep appeared. In contrast, morphine challenge to post-addict rats was followed by an EEG and behavioral arousal for as long as 180 min, the degree of which was less pronounced at the longer intervals following withdrawal. The EEG and behavioral arousal of the post-addict rat in response to morphine challenge is reminiscent of similar responses in human postaddicts already reported and may further emphasize the pharmacodynamic factors in morphine addiction.
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Supported by NIMH Grant MH-16693; a preliminary report on this work appeared in Fed. Proc. 30, 277, (1971).
NIMH Postdoctoral Fellow.
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Khazan, N., Colasanti, B. EEG correlates of morphine challenge in post-addict rats. Psychopharmacologia 22, 56–63 (1971). https://doi.org/10.1007/BF00401467
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DOI: https://doi.org/10.1007/BF00401467