MINOCYCLINE PREVENTS CHRONIC STRESS-INDUCED VULNERABILITY TO COCAINE SELF-ADMINISTRATION

AVALOS MARIA PAULA; BOLLATI FLAVIA; RIGONI DAIANA; GUZMAN ANDREA SUSANA; CANCELA LILIANA M

Mar del Plata

Congreso; XXXII Congreso de la Sociedad Argentina de Investigación en Neurociencias. Congreso International; 2017

Sociedad Argentina de Investigación en Neurociencias

Clinical evidence supports the idea of individuals that suffer stressing events along their lives are vulnerable to developing substance use disorders (SUDs). Here, we demonstrated how exposure to chronic stressful life events can facilitate the acquisition of cocaine selfadministration (SA). We also attempted to prevent SA behavior by minocycline pretreatment. Thus, rats were exposed to chronic restraint stress (2 hs daily) during seven days. A week after that, animals were implanted with indwelling jugular catheters. A week aftersurgery, rats began daily 2 hs cocaine SA sessions for ten days. Four days before the onset of SA paradigm, the minocycline (30 mg/kg/12hs) or vehicle (DMSO 5%) daily treatments started, which were carried out until the end of the SA behavior. SA consists of a fixed ratio 1 schedule (FR 1) in which one response on the active lever yielded one intravenous cocaine infusion (0.2 mg/infusion, followed by a 10 s timeout period), paired with a tone and a lightcue. An inactive lever was also available each session. SA criterion was defined as the first day animals obtaining more than ten infusions of cocaine. Our results point out a facilitation of the acquisition of cocaine SA as well an augmented intake of cocaine induced by chronic stress, which was interestingly abolished by minocycline. These findings constitute a starting platform to study the mechanisms underpinning the comorbility between stress and SUDs.