A LONG ABSTINENCE PERIOD AFTER A LOW, CHRONIC ETHANOL EXPOSURE DOES NOT RESULT IN A FULL RECOVERING OF NEURONAL MORPHOLOGY

EVRARD, SG; DUHALDE VEGA, M; TAGLIAFERRO, AP; MIROCHNIC, S; CALTANA, L; BRUSCO, A

Viña del Mar, Chile

Congreso; II Neurotoxicity Society Meeting; 2005

There are few morphological studies on EtOH exposure and recovery after a long abstinence. We evaluated neurons long after drinking cessation of a low EtOH dose. Adoles-cent male Wistar rats were exposed to EtOH 6.6% v/v in drinking water for 6 weeks and studied after ending exposure or after a 10-week recovery period drinking water. Brain sections were ìmmunostained using antibodies to MAP-2; 200 kDa neurofilaments; neuronal nitric oxide synthase and 5-HT. We studied by image analysis: hippocampal CA1 area, striatum and frontal cortex; the dorsal and median raphe nucleus. The relative area covered by MAP-2+ and Nf-200+ fibers decreased in all the studied areas after EtOH exposure and differentialy recovered after the abstinence period. Immunoreactivity of 5-HT+- and nNOS+-neurons were also altered, after EtOH exposure or after abstinence. Conclusion: to stop drinking can partially ameliorate EtOH-induced morphological changes but cannot fully restore the basal state.