STRESS EFFECTS ON ANXIETY IN FEMALE RATS AT DIFFERENT STAGES OF ESTRUS CYCLE

Locomotor activity in the elevated plus-maze was studied in female whi te rats following chronic stress induction (measuring pain threshold i n the course of 15-20 days). Anxiety and plasma corticosterone levels were determined. In control experiments in intact rats anxiety was low er and locomotor activity was higher in proestrus than in diestrus. Th ere were no differences in anxiety and locomotor activity between dies trus and proestrus in rats exposed to chronic stress. In intact rats p lasma corticosterone levels were the same in proestrus and diestrus. F ollowing chronic stress plasma corticosterone level was significantly higher in proestrus than in diestrus.