Involvement of limbic neuronal corticosterone in the regulation of arterial blood pressure

The effect of experimentally induced blood pressure changes on the in vivo release of neuronal corticosterone in limbic and hypothalamic areas was studied in anaesthetized rats. A fall of the arterial blood pressure (ABP) elicited by the intravenous (i.v.) injection of the vasodilatator nitroprusside or the ganglionic blocking agent chlorisondamine decreased the release of corticosterone in the central amygdala (AC) and the ventral hippocampus (VH) whereas an experimentally induced hypertension after i.v. administration of the alpha adrenoreceptoragonist tramazoline led to an enhanced release of the glucocorticoid in the limbic areas mentioned above. Alterations in ABP did not affect the rates of corticosterone release in the medial hypothalamus (MH). The results may indicate a functional role for neuronal limbic corticosterone in central blood pressure regulation.