Psychological stress enhances noradrenaline turnover in specific brain regions in rats.
Concentrations of noradrenaline (NA) and 3-methoxy-4-hydroxyphenylethyleneglycol sulfate (MHPG-SO4) in the hypothalamus, amygdala, cerebral cortex and pons + medulla oblongata were examined in male Wistar rats exposed to foot-shock or to psychological stress for 1 hour. Animals in the psychological stress group were prevented from receiving foot shock, but were exposed to responses of shocked rats. Foot shocked rats exhibited a significant reduction in NA content and a significant elevation in MHPG-SO4 level in all brain regions when compared to control rats which were neither shocked nor exposed to shocked rats. Rats exposed to the psychological stress displayed a significant reduction of NA level in the amygdala, significant elevation of MHPG-SO4 content in the hypothalamus and amygdala, and a moderate elevation of plasma corticosterone level. These results suggest that psychological stress produces mild enhancement of NA release preferentially in the hypothalamus and amygdala; while foot shock stress elicits a more intense response of noradrenergic neurons in more extended brain regions.
D000679:Amygdala / Q000378:metabolism; D000818:Animals; D001921:Brain / Q000378:metabolism*; D001933:Brain Stem / Q000378:metabolism; D002540:Cerebral Cortex / Q000378:metabolism; D006801:Humans; D007031:Hypothalamus / Q000378:metabolism; D008297:Male; D008734:Methoxyhydroxyphenylglycol / Q000378:metabolism; D009638:Norepinephrine / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D013315:Stress, Psychological / Q000378:metabolism*
D008734:Methoxyhydroxyphenylglycol; D009638:Norepinephrine