NORADRENERGIC-GABAERGIC INTERACTION IN ANTERIOR HYPOTHALAMUS FROM NORMOTENSIVE AND SINOAORTIC DENERVATED RATS

1. GABA content is decreased in anterior hypothalamus and medulla oblo ngata of hypertensive rats by sinoaortic denervation (SAD) when compar ed to control animals which underwent a sham-operation (sham). 2. Lesi on of noradrenergic pathways by 6-hydroxydopamine (6-OHDA), intracereb roventricularly administered, induced depletion of noradrenergic conte nt in frontal cortex, anterior and posterior hypothalamus in both SAD and sham-operated rats. 3. As a consequence of this noradrenergic depl etion there was an increase of GABA content in anterior hypothalamus o nly, from sham- and SAD-operated animals, without changes in other are as. 4. There is a noradrenergic-GABAergic interaction in the anterior hypothalamus of normotensive rats which is not impaired in hypertensiv e rats by sinoaortic denervation.