Early exposure to chronic variable stress facilitates the occurrence of anhedonia and enhanced emotional reactions to novel stressors: reversal by naltrexone pretreatment

ZURITA A, MARTIJENA I, CUADRA G, LIRA BRANDAO M, MOLINA VA

ELSEVIER SCIENCE BV

Año: 2000 p. 163 - 163

b> Abstract The present research studied the influence of an early chronic variable stress (CVS) paradigm ? an animal model of depression ? on behavioral responses to subsequent environmental challenges suggested to model anhedonia and emotional reactions such as anxiety and fear. In order to explore a potential involvement of an endogenous opiate mechanism ? presumably activated during CVS exposure ? in the development of such behavioral reactions, in all experiments rats were administered naltrexone (NAL, 2 mg:kg, i.p.) or vehicle (VH) prior to each daily stressor of the C