大鼠延髓外侧网状旁巨细胞核的去甲肾上腺素在针刺镇痛中的作用

EFFECT OF NOREPINEPHRINE IN IN RAT'S NUCLEUS RETICULARIS PARAGIGANTOCELLULARIS LATERALIS DURING ACUPUNCTURE ANALGESIA

用脑立体定位技术及微量注射方法，分别将去甲肾上腺素（ＮＥ）能ａ受体拮抗剂酚妥拉明，β受体拮抗剂心得安，非选择性激动剂ＮＥ微量注入大鼠延髓外侧网状旁巨细胞核（ＲＰＧＬ），观察ＲＰＧＬ中ＮＥ在针刺镇痛中作用。结果表明，酚妥拉明有加强针刺镇痛作用（Ｐ＜０．０２），ＮＥ则有对抗针刺镇痛效应（Ｐ＜０．０１），而心得安对针刺镇痛影响不大。ＲＰＧＬ中ＮＥ的对抗针刺镇痛作用可能通过ａ受体来实现的。

The aim of this experiment was to investigate the role of NE in RPGL at the postsynaptie level during acupuncture analgesia(AA). After 20 minutes of electroaeupuncture(EA),the pain threshold of rats was markedly elevated and at the 20th of EA, NE(1g/0.5L,2min) was microinjected into RPGL, It was fonnd that the effect of AA was partially reversed by NE(P<0. 05),In high effective aoupuncture group, phentolamine(2.5g/0.5L,2min), an alpha antagonist, microinjected into RPGL at the 20th minute of EA could enhance the effect of AA(P<0.02), but no singnificant changes were found in low effective acnpunctnre group. Propranolol(2.5g/0.5L,2min), a beta antagonist, has no effect on AA in either high or low effective acupuncture group. The results suggest that activation of alpha receptor in the RPGL has an antagonistic effect on AA.