Ethanol withdrawal induces a variety of emotional disturbances and facilitates the onset of a negative affective state that can persist even after a prolonged period of abstinence. Fear is an emotional response that could be implicated in the development of this state. The goal of the present study was to investigate the influence of the ethanol withdrawal on fear, as an expression of associative and nonassociative aversive learning.
Adult maleWistar rats were submitted to chronic treatment with an ethanol liquid diet during 14 days (2 days with ethanol 6% v/v and 12 days 8% v/v). These animals were exposed to 3 inescapable electrical footshocks (0.7 mA, duration 3 s) to evaluate the conditioned fear response, during different abstinence periods (3, 7, and 13 days).
The freezing response, as a behavioral expression of fear, was evaluated 24 h after the shock session in the context previously paired these unconditioned stimuli. This response was also evaluated in a novel unpaired context as a behavioral output of unconditioned fear learning.
Animals previously exposed to ethanol withdrawal showed an enhanced fear response that persists until day 14 of abstinence and could be due to an incapacity to extinguish such freezing response, only in the conditioned context.
