[The inhibitory effects of stimulating AC, AL, BNST and AHL on visceral pain].

We took the unit discharges of the neurons in the posterior group of thalamic nuclei (PO) caused by stimulating the great splanchnic nerve (GSN) as an indicator of visceral pain. We searched for the effects of electrical stimulating central nucleus of amygdala (AC), lateral nucleus of amygdala (AL), bed nucleus of striae terminalis (BNST) and lateral area of hypothalmus (AHL) on unit discharges of PO and the relationship among these nucleuses. The result indicated that the inhibitory effects were strongest with stimulating AC, the next was with stimulating AHL, then BNST and AL. The inhibitory percentages were 85.7% (AC), 62.9% (AHL), 53.1% (BNST) and 54.2% (AL) respectively. The inhibitory effects of stimulating AC couldn't be canceled by injecting naloxone intravenously. AC may be more important for the antinociceptive system than AL, BNST and AHL. There was no relationship between AC and BNST on the inhibition of unit discharges. The inhibitory effects of stimulating AL may be related to AC.