[Role of nucleus parabrachialis medialis in the "renzhong" induced pressor response in rabbits].

Experiments were performed on 18 rabbits, bivagotomized, gallamine triethiodide immobilized and artificially ventilated. The effects of electrical stimulation of "renzhong" (Du 26) area and NPBM, separately and simultaneously, on arterial blood pressure and heart rate were observed before and after electrolytic or chemical lesion of NPBM. Electrical stimulation of "renzhong" area or NPBM, separately could elicit an increase in arterial blood pressure; when both "renzhong" and NPBM were stimulated, the pressor response to NPBM stimulation could affect that of "renzhong" area's. But after electrolytic or chemical lesion of NPBM, stimulation of NPBM could no longer elicit pressor response. On the other hand, the pressor response induced by electrical stimulation of "renzhong" area decreased obviously, after lesion of NPBM or transection of brain stem between NPBM and Nucleus trigemini principalis. These results suggest that NPBM might take part in the pressor response of "renzhong" area stimulation.