Undergraduate Honors Theses

Thesis Defended

Spring 2019

Document Type


Type of Thesis

Departmental Honors


Psychology & Neuroscience

First Advisor

Dr. Ryan Bachtell

Second Advisor

Dr. Michael Saddoris

Third Advisor

Dr. Jacquline Richardson


Cocaine and oxycodone addictions are chronic, relapsing disorders characterized by maladaptive patterns of drug seeking that create significant impairment for the user. While the homeostatic functions of neuroimmune cells such as microglia and astrocytes have been well characterized, little work has examined the structural and functional alterations of these neuroglial cells following repeated drug intake. The first experiment of this study used male and female Sprague-Dawley rats to examine sex differences in microglial cells following repeated cocaine intake. The second experiment used a rodent model of oxycodone self-administration to test the ability of ibudilast, a non-selective anti-inflammatory drug, to reduce drug seeking behavior following 14 days of forced abstinence. The present study found no apparent difference in markers of microglial activity between males and females following cocaine intake. Further, it was demonstrated that administration of ibudilast attenuates incubation of oxycodone craving following 14 days of forced abstinence. This was accompanied by a reduction in markers of astrocyte, but not microglial, activity in the ventral tegmental area and nucleus accumbens. These results are consistent with the hypothesis that drug-induced neuroinflammation contributes to heightened oxycodone craving and seeking following a prolonged period of abstinence.