THE EFFECTS OF DORSAL AND VENTRAL NORADRENERGIC SYSTEM LESIONS WITH DSP-4 ON EMOTIONAL-DEFENSIVE BEHAVIOR AND REGIONAL BRAIN MONOAMINES CONTENT IN THE CAT

As a result of selective lesions of dorsal (DB) and ventral (VB) norad renergic system (DSP-4 i.c.) it was observed that these two systems ar e functionally differentiated and only DB participates in the regulati on of post-carbachol emotional-defensive behavior in the cat. Followin g DB lesion an increase in emotional-defensive excitation occurred and HPLC analysis showed a significant reduction of NA concentration in t he posterior hypothalamus, midbrain central gray matter and frontal co rtex and decreased turnover of 5-HT in all ''emotional brain areas'' ( hypothalamus, midbrain, amygdala, hippocampus) and frontal cortex. Fol lowing VB lesion there were no significant changes of post-carbachol d efensive behavior and HPLC analysis showed a significant reduction of NA in the anterior and posterior hypothalamus, midbrain central gray m atter and amygdala and an increased turnover of 5-HT in the posterior hypothalamus and midbrain central gray matter. The results obtained ca n be interpreted in relation to functional interactions between the NA and 5-HT systems.