Cocaine-induced stroke susceptibility: motor and cognitive outcomes




Taylor, Cynthia
Vann, Philip
Li, Wenjun
Forster, Michael
Yang, Shaohua
Sumien, Nathalie


Journal Title

Journal ISSN

Volume Title



Title: Cocaine-induced stroke susceptibility: motor and cognitive outcomes Presenters: Philip Vann, Cynthia Taylor, Wenjun Li, Michael J. Forster, Shaohua Yang, Nathalie Sumien Purpose: Epidemiological findings suggest that the number of young individuals suffering from stroke seems to be increasing, and one of the most common cause for such an increase is the use of illicit drugs. Prior work in our laboratory suggested that life-long cocaine intake impaired cognitive function and that short-term intake induces brain changes conferring vulnerability. In this study, we tested the hypothesis that repeated cocaine use will induce brain vulnerability to ischemic stroke. Methods: Fifty seven young male Sprague-Dawley rats (3 months) were injected i.p. with cocaine (10mg/kg) or saline (3 times/wk) for 4 weeks. From each treatment group, half of the rats received an ischemic stroke (transient Middle Cerebral Artery Occlusion) and the other half a sham surgery. After a one month recovery period, the rats were subjected to a behavioral battery of tests measuring balance, motor function, spatial learning and long term memory (locomotor activity, bridge walking, rotorod, and Morris water maze). Once behavioral testing was finalized the rats were euthanized and brain regions were collected for further biochemical analyses. Data were analyzed using 2- or 3-way ANOVAs followed by pairwise comparisons. Results: The stroke surgery resulted in decreased body weights and increased overall activity (total distance travelled and horizontal activity). Maximum performance on the rotorod was lower for the stroked rats than for the shams, and treatment with cocaine did not affect the outcome. However, during training the cocaine-treated rats had higher latencies than the controls. On the bridge walking test, the stroke surgery did not seem to affect performance, however the cocaine-treated stroke rats performed the worst. The stroked rats took longer path length and latencies to reach the platform, and cocaine seem to exacerbate the impairment, more specifically at the end of training and during retention. Conclusions: While preliminary, these results suggest that cocaine-treated rats were more vulnerable to stroke than the saline-treated ones but exhibiting exacerbated impairments on balance and spatial learning and memory. Studies to identify the underlying mechanisms of this vulnerability are underway. IACUC 2016-0022 Intramural grant UNTHSC RI10014