大鼠中央灰质Fos蛋白与甲啡肽的共存

COLOCALIZATION OF Fos PROTEIN AND METENKEPHALIN IN PERIAQUEDUCTAL GRAY IN RATS

用免疫组织化学方法观察福尔马林脚掌皮下注射和足三里穴电针后清醒大鼠中脑导水管周围灰质（ＰＡＧ）中快速反应基因ｃ－ｆｏｓ在含甲啡肽神经元中的表达。实验中看到福尔马林注射组和电针刺激组动物的ＰＡＧ内均有Ｆｏｓ样免疫阳性反应（ＦＬＩ）标记神经元及ＦＬＩ与甲啡肽样免疫阳性反应（ＭＥＬＩ）双标记神经元，它们在ＰＡＧ的腹侧腹外侧部分布较多，对照动物ＦＬＩ标记神经元很少，共存现象极为少见。实验组与对照组神经无计数经统计处理差异非常显著。这一结果表明，福尔马林致痛和电针都能诱导ＰＡＧ中含脑啡肽神经元内（ｃ－ｆｏｓ的表达，提示伤害性刺激及针刺均可激活ＰＡＧ的腹侧腹外侧部这一重要的中枢镇痛部位。神经元中ＦＬＩ与ＭＥＬＩ的并存提示ＰＡＧ中Ｆｏｓ可能对前脑啡肽原基因表达有调控作用。

The expression of the immediate early gene c-fos in met-enkephalin-containing neurons of the periaqueductal gray(PAG)in conscious rat after hind paw formalin in jection or electroacupuncture(EA)of'Tsu San Li' were determined by immunocytochemical method.Labeling neurons of Fos-like immunoreactivity(FLI)and double labeling neurons of FLI and met-enkephalin-like immunoreactivity(MELI)were seen in the PAG in both formalin and EA group.More labeling neurons were distributed in the ventral and ventrolateral part of the PAG. The control group showed very low FLI level and double labeling was rare.There is a significant difference between the experiment and control groups.The results indicate that both formalin nociception and EA can induce c-fos expression in met-enkephalin-containing neurons in the PAG,and sugget that both stimuli can activate the ventral and ventrolaoeral part of the PAG,a central locus critical to analgeaia.The colocalization of FLI and MELI suggests that Fos may regulate the expression of preproenkephalin gene in the PAG.