ROLE OF LATERAL PARABRACHIAL NUCLEUS IN THE INHIBITION OF WATER-INTAKE PRODUCED BY RIGHT ATRIAL STRETCH

Rats with either bilateral electrolytic or sham lesions of the ventrol ateral portion of the lateral parabrachial nucleus (VLLPBN) were impla nted with latex balloons that lay at the right superior vena cava/atri al junction (RSVC/AJ). Water intake in response to isoproterenol was m easured both with and without inflation of the balloon. Water intake o f the sham-lesioned rats was significantly depressed by balloon inflat ion during the first hour of the experiment. In contrast, water intake in the VLLPBN-lesioned rats was unaffected by balloon inflation. Thes e results suggest that the VLLPBN is involved in the processing of aff erent input from stretch-activated RSVC/AJ receptors.