Chronic stress increases the reactivity of central depressor mechanisms
Zaretskiĭ, D.V.; Zaretskaia, M.V.; Livanova, L.M.; Kalenikova, E.I.; Kuz'min, A.I.; Aĭrapetiants, M.G.; Chazov, E.I.
Rossiiskii Fiziologicheskii Zhurnal Imeni I.M. Sechenova 85(6): 819-825
1999
ISSN/ISBN: 0869-8139 PMID: 10512002 Document Number: 505737
The activity of noradrenergic system of lateral hypothalamus and hemodynamics were studied during acute restraint in chronically stressed and control rats. Arterial blood pressure in rest was negatively proportional to basal norepinephrine concentration in dialysate of lateral hypothalamus. Animals with high increase of norepinephrine levels in dialysate during acute stress had rapid return of arterial blood pressure to basal values while stress-induced hypertension in the beginning of restraint was the same as in rats with low increase of norepinephrine levels. Data obtained show the depressor role of noradrenergic system of lateral hypothalamus. The enhanced reactivity of noradrenergic depressor system may be one of the mechanisms providing cardiovascular adaptation to stress.