In:
European Journal of Neuroscience, Wiley, Vol. 50, No. 3 ( 2019-08), p. 2101-2112
Abstract:
Each year, traumatic brain injuries ( TBI ) affect millions worldwide. Mild TBI s ( mTBI ) are the most prevalent and can lead to a range of neurobehavioral problems, including substance abuse. A single blast exposure, inducing mTBI alters the medial prefrontal cortex, an area implicated in addiction, for at least 30 days post injury in rats. Repeated blast exposures result in greater physiological and behavioral dysfunction than single exposure; however, the impact of repeated mTBI on addiction is unknown. In this study, the effect of mTBI on various stages of oxycodone use was examined. Male Sprague Dawley rats were exposed to a blast model of mTBI once per day for 3 days. Rats were trained to self‐administer oxycodone during short (2 h) and long (6 h) access sessions. Following abstinence, rats underwent extinction and two cued reinstatement sessions. Sham and rb TBI rats had similar oxycodone intake, extinction responding and cued reinstatement of drug seeking. A second group of rats were trained to self‐administer oxycodone with varying reinforcement schedules (fixed ratio ( FR )‐2 and FR ‐4). Under an FR ‐2 schedule, rb TBI ‐exposed rats earned fewer reinforcers than sham‐exposed rats. During 10 extinction sessions, the rb TBI ‐exposed rats exhibited significantly more seeking for oxycodone than the sham‐injured rats. There was a positive correlation between total oxycodone intake and day 1 extinction drug seeking in sham, but not in rb TBI ‐exposed rats. Together, this suggests that rb TBI ‐exposed rats are more sensitive to oxycodone‐associated cues during reinstatement than sham‐exposed rats and that rb TBI may disrupt the relationship between oxycodone intake and seeking.
Type of Medium:
Online Resource
ISSN:
0953-816X
,
1460-9568
Language:
English
Publisher:
Wiley
Publication Date:
2019
detail.hit.zdb_id:
2005178-5
SSG:
12
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