双侧损毁腹外侧眶皮层对电针抑制大鼠甩尾反射的影响

Effects of Bilateral Lesions of Ventrolateral Orbital Cortex on the Rat Tail Flick Reflex Inhibition Evoked by Electroacupuncture

本研究在浅麻大鼠发现，电解损毁双侧腹外侧眶皮层（VLO）明显减弱强电针“足三里”穴对大鼠甩尾（TF）反射的抑制效应；但对弱电针的抑制效应无明显影响。表明VLO参与伤害感受调制，它可能在强电针兴奋细纤维（Ⅲ、Ⅳ类）产生的镇痛中具有重要作用。本研究为我们提出的脊髓-丘脑中央下核（Sm）-VLO-导水管周围灰质（PAG）-脊髓负反馈痛调制环路的设想提供了支持。

This study found that bilateral electrolytic lesions of the ventrolateral orbital cortex(VLO)markedly reduced the inhibitory effects of high intensity electroacupuncture (EA) at 'Zusanli'point on tail flick reflex in lightly anesthetized rats, but did not influence the inhibitory effects of low intensity EA stimulation. The results show that the VLO is involved in acupuncture analgesia produced by activation of snlall afferent fibers with high intensity electroacupunture. Results of this study provide further support for a hypothesis that spinal cord-Sm-VLO-PAG-spinal cord may constitute a negative feedback loop of nociceptive rnodulation. The analgesic effects produced by high intensity electroacupuncture may be mediated by this loop leading to depression of the nociceptive inputs at the spinal cord level.