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BACKGROUND AND AIMS: The central nucleus of the amygdala (CeA) has efferent projections to regions involved in autonomic, endocrine, and behavioral responses to emotional stimuli. Due to its role in the regulation of the activity of corticosterone releasing factor (CRF) neurons in the paraventricular nucleus of the hypothalamus (PVN), the CeA is considered a key modulator of behavioral responses to stress. Examine how electrical stimulation of the CeA, which is known to participate in the integration of sensory and emotional informations with neuroendocrine responses, influences stress-related behaviors and plasma corticosterone level in rats. METHODS: Male Wistar rats implanted under standard stereotaxic surgery with stimulating electrodes into the CeA were divided into the following groups: CeA 14–day electrical stimulation (n=12) and CeA sham (n=10) – control, no stimulation. Behavioral activity during the 5-min testing period in the elevated plus maze (EPM) was recorded and analyzed (e.g. number of entries into closed arms, time spent in open arms). Additionally episodes of grooming were measured. Blood samples were collected by heart puncture (isoflurane anesthesia) seven days before (basal), one hour and seven days after the last stimulation. The plasma corticosterone level (CORT) was determined by radioimmunoassay. RESULTS: Stress-related activity in the EPM and grooming episodes were increased in stimulated rats after last stimulation. Whereas the control group showed gradual adaptation to the testing conditions which was manifested by decreased behavioral activity. Effects of CeA stimulation were also confirmed by an increase in plasma corticosterone level. CONCLUSIONS: Electrical stimulation of the CeA induces stressrelated behavior which is reflected by active avoidance of stressful situation (escape behavior) and adaptive activities to stressful conditions (grooming). Research was supported by The National Science Centre, grant number: NN303819040.