【摘要】 本实验用玻璃微电极细胞外记录神经元单位放电的方法观察了侧脑室注射纳洛酮前后刺激大鼠皮层体感运动Ⅱ区（SmⅢ）对丘脑特异性核团腹侧基底核（VB）神经无伤害性反应的影响。结果表明：单纯刺激SmⅡ可抑制VB神经元的伤害性反应；侧脑室注射纳洛酮后，SmⅡ对丘脑VB神经元伤害性反应的下行抑制效应被减弱。提示：皮层SmⅡ对丘脑VB有下行调节作用。内源性阿片肽可能是皮层下行调节疼痛的递质之一。更多还原

【Abstract】 The effect of opioid peptides on corticofugal modulation of nociceptive response in thalamic ventrobasal nucleus (VB) produced by cortical sensorimotor area Ⅱ (Sm Ⅱ) was observed.Single unit activities of VB neurons were extracellularly recorded by glass microelectrodes.The results showed that the nociceptive responses of VB neurons were attenuated at 0- 7. 5 minutes after stimulating Sm Ⅱ(n=14, P<0.05). The inhibitory effect of stimulation of Sm Ⅱ was reduced after ventriculer microinjection of 20ul of naloxone (n=9), while marked inhibition was shown at 0- 2. 5 minutes after stimulating Sm Ⅱ in the saline control group (n= 9, P<0.05). There was a statistical difference at 0 - 2. 5 minutes after stimulating Sm Ⅱ between the two groups (P<0.05). These studies suggest that opioid peptides might be involved in corticofugal modulatio of pain更多还原