Abstract: It is well known that the β-endorphin-containing neurons,serotonin-containing neurons and noradrenaline-containing neurons are concentrated inhypothalamic arcuate nucleus,dorsal raphe nucleus and locus coeruleusrespectively.In this study the effects of lesion of these three nuclei onstress-induced analgesia were investigated in rats.Stress was produced byinescapable intermittent footshock,and the analgesic effect was measuredby tail stimulation-vocalization test. After monosodium glutamate-induced arcuate nuclear lesion and kainicacid-induced lesion or electrolytic lesion of dorsal raphe nucleus and locuscoeruleus,the analgesic effect of footshock stress was decreased significantly.It is suggested that β-endorphin-,serotonin-and noradrenaline-containingneurons might play an important role in stress-induced analgesia.

Key words: NULL