Effect of transection in the brainstem on short-term maintenance of deoxycorticosterone-salt hypertension

Sections were made to determine supraspinal areas that participate in the maintenance of deoxycorticosterone (DOC)-salt hypertension. Blood pressure (BP) falls after cuts which severed: (a) the lateral connections between pons and midbrain, (b) the pathways between caudal hypothalamus and midbrain, and (c) parasagittal connections between medial and lateral hypothalamus. No changes in BP were found either after coronal cuts that severed a central area located at: (a) the pons-midbrain edge, (b) above the caudal hypothalamus, and (c) the level of the anterior hypothalamic area, or after parasagittal cuts at the level of the capsula interna or after a hypophysial stalk lesion. These results implicate the hypothalamus in the maintenance of DOC-salt hypertension. The hypothalamus-neural lobe system appears not to be involved in the lowering of BP found.