HIV ‐1 Tat and morphine interactions dynamically shift striatal monoamine levels and exploratory behaviors over time

To examine the relationship between opioid and HIV-1-induced alterations in striatal monoamine concentrations and behavior, morphine was administered to HIV-1 Tat transgenic mice for 2  weeks or 2 months. Morphine and Tat interacted to alter levels of dopamine, dopamine metabolites, norepinephrine, and 5-hydroxyindoleacetic acid depending on the duration of exposure and neurotransmitter/metabolite assayed. Co-exposure to Tat and morphine disrupted locomotor activity in a time- dependent manner. Alternatively, Tat alone inhibited social exploratory behavior, whereas morphine alone tended to increase novelty-seeking behavior. The data suggest that Tat and morphine effects on monoamine neurochemistry are complex and contribute to motor and exploratory behavioral dysregulatio n. AbstractDespite the advent of combination anti-retroviral therapy (cART), nearly half of people infected with HIV treated with cART still exhibit HIV-associated neurocognitive disorders (HAND). HAND can be worsened by co-morbid opioid use disorder. The basal ganglia are particularly vulnerable to HIV-1 and exhibit higher viral loads and more severe pathology, which can be exacerbated by co-exposure to opioids. Evidence suggests that dopaminergic neurotransmission is disrupted by HIV exposure, however, little is known about whether co-exposure to opioids may alter neurotransmitter levels in the striatum and if this in turn influences behavior. Therefore, we assayed motor, anxiety-like, novelty-seeking,...
Source: Journal of Neurochemistry - Category: Neuroscience Authors: Tags: ORIGINAL ARTICLE Source Type: research