Differential brain expression of catalase in developmentally-Pb-exposed rats that have voluntarily consumed ethanol

MATTALLONI M; CANCELA LM; VIRGOLINI MB

Buenos Aires

Congreso; 2nd FALAN Congress; 2016

FALAN

Differential brain expression of catalase in developmentally-Pb-exposed rats that have voluntarily consumed ethanolLead (Pb) is a developmental neurotoxicant that modifies several responses to ethanol, with a demonstrated participation of the brain ethanol-to-acetaldehyde-metabolizing enzyme catalase (CAT) in these effects. At this respect, we have shown that perinatal low-level Pb exposure increases voluntary ethanol intake, effect that was blunted by a CAT inhibitor (aminotriazole -AT) and further increased by a CAT booster (3-nitropropionic acid -3NPA). The present study was aimed to evaluate CAT expression in limbic brain regions (nucleus accumbens, frontal cortex and striatum) in animals that have been developmentally exposed to low Pb levels, and at peridolescence offered to drink water or increasing ethanol concentrations: 2-10%, during 28 days. Immediately after the last free-choice session and corresponding pharmacological treatment (AT, 250 mg/kg i.p. or 3NPA, 20 mg/kg s.c.), all rats were sacrificed and brain regions harvested to measure brain CAT expression by immunohistochemistry. The results demonstrated that the Pb-exposed rats that voluntary consumed more ethanol evidenced higher CAT expression in limbic areas related to both, controls and their non-ethanol counterparts. In relation to the pharmacological treatments, AT reduced, while 3NPA failed to increase CAT expression in limbic areas. These results emphasize the importance of CAT as a key component of ethanol metabolism, ascribing a critical role to brain acetaldehyde in the Pb-induced ethanol-reinforcing effects.