Acute hypertension increases norepinephrine release in the diagonal band of Broca

In vivo microdialysis was used to measure extracellular concentrations of norepinephrine in the diagonal band of Broca (DBB) during changes in blood pressure in conscious rats. Dialysate norepinephrine concentration was significantly increased during acute hypertension (280±40% of control), but was not changed by hypotensive hemorrhage. These results are consistent with the proposal that noradrenergic innervation of the DBB is selectively activated by increased blood pressure.