cPKCs在大鼠内脏炎性痛形成中的作用

目的 探讨cPKCs在大鼠内脏炎性痛形成中的作用.方法 成年Wistar大鼠96只,体重200～250 g,雌雄不拘.随机分为4组(n=24):对照组(C组)、生理盐水组(NS组)、PMA组和H-7组.大鼠蛛网膜下腔置管后,采用直肠粘膜下注射福尔马林的方法,制备大鼠内脏炎性痛模型.C组不给予任何处理,NS组、PMA组、H-7组分别于给予福尔马林前30 min经PE-10管注射0.9%生理盐水20 μl、cPKCs和nPKCs激动剂PMA 100 ng(生理盐水稀释至20 μl)、PKC抑制剂H-7 200 μg(生理盐水稀释至20 μl),然后分别注入0.9%生理盐水10 μl冲洗PE-10管.各组于给予福尔马林后30、60、120 min时取8只大鼠,测定内脏痛评分,然后取脊髓,测定cPKCs膜转位水平.结果 与NS组比较,给予福尔马林后30、60 min时PMA组内脏痛评分升高,H-7组内脏痛评分降低(P＜0.05或0.01).与C组比较,NS组给予福尔马林后30 min时PKCγ膜转位水平升高,PMA组给予福尔马林后30、60 min时PKCγ膜转位水平升高(P＜0.01).与Ns组比较,给予福尔马林后30、60 min时PMA组PKCγ膜转位水平升高,H-7组PKCγ膜转位水平降低(P＜0.05).结论 cPKCs型的PKCγ亚型参与了大鼠内脏炎性痛的形成.

The role of cPKCs in visceral inflammatory pain in rats

Objective To investigate the role of cPKCs in visceral inflammatory pain in rats.Methods Ninety-six adult Wistar rats of both sexes weighing 200-250 g were randomly divided into 4 groups(n=24 each):group Ⅰ control(C);group Ⅱ normal saline(NS);group Ⅲ PMA(nPKCs and cPKCs agonist)and group Ⅳ H-7(PKC antagonist).The animals were anesthetized with intraperitoneal pentobarbital 40 mg/kg.A PE-10 catheter was placed in the subarachnoid space with the tip at lumbar region.Visceral inflammatory pain(VIP)was induced by injecting 5% formalin 100 μl underneath the mucous membrane of rection.The control group received nothing via spinal catheter.Normal saline 20 μl,PMA 100 ng(in 20 μl NS) and H-7 200 μg(in 20 μl NS)were injected into the subarachnoid space through the spinal catheter in group Ⅱ,Ⅲ and Ⅳ respectively 30 min before rectal submucosal formalin injection.VIP was assessed at 30(T1),60(T2) and 120 (T3) min after formalin injection by a numerical scoring system according to Zhang(the higher the number the severer the pain).Eight animals in each group were killed at the 3 time points after pain behavior assessment,and the lumbar region of the spinal cord(L6-S1,2)for determination of the level of spinal cord cPKCs membrane translocation.Results The pain scores at T1 and T2 were significantly higher in PMA group and lower in H-7 group than in NS group.The levels of PKCγ membroxle translocation at T1 and T2 were significantly higher in PMA group and lower in H-7 group than in NS group.Conclusion PKCγ subtype of cPKCs may be involved in the mechanism of visceral inflammatory pain.