摘要
目的探讨脊髓α2-肾上腺素能受体在异丙酚抗大鼠内脏性伤害刺激中的作用。方法雄性成年大鼠，进行蛛网膜下腔置管，3～5d后鞘内置管成功的28只大鼠于结直肠放置气囊，随机分为4组（n=7），Ⅰ组和Ⅱ组鞘内注射生理盐水（NS）10μl后10min，分别腹腔注射NS 0．5ml或异丙酚10mg／kg；Ⅲ组和Ⅳ组鞘内注射育亨宾15μg后10min，分别腹腔注射NS 0．5ml或异丙酚10mg／kg。分别于鞘内给药前及注射异丙酚后5、10、15、20、25、30、40和60min时进行气囊充气，测定内脏痛阈，计算最大镇痛效应百分率（MPE）。结果与Ⅰ组比较，Ⅱ组和Ⅳ组MPE升高（P〈0．05或0．01）；与Ⅱ组比较，Ⅳ组MPE降低（P〈0．01）。结论脊髓α2-肾上腺素能受体激活参与了异丙酚抗大鼠内脏性伤害刺激反应。
Objective To investigate the role of spinal cord α2-adrenoceptor in the antinociceptive effects of propofol in rats. Methods Male SD rats weighing 190-260 g were anesthetized with introperitoneal （IP） chloral hydrate 400 mg/kg. Intrathecal （IT） catheter was placed at L3,4 interspace according to Yang. Animals which were lame and paralyzed and locally infected after IT catheterization were excluded. A Latex balloon was inserted into desending colon and rectum. Visceral pain was induced by inflating air into the balloon until flattening of the abdominal muscle and the abdomen was lifted from the surface of the table. The threshold of visceral pain was assessed by the intra-balloon pressure which was limited to 80 mm Hg to avoid damage to intestine. Twenty-eight animals in which IT catheters were successfully placed were randomly divided into 4 groups （ n = 7 each） ： group Ⅰ normal saline （NS） 10 μl IT ＋ NS 0.5 ml IP; group Ⅱ NS 10 μl IT ＋ propofol 10 mg/kg IP; group Ⅲ yohimbine 15 μg IT ＋ NS 0.5 ml IP and group Ⅳ yohimbine 15 μg ＋ propofol 10 mg/kg. The IT NS/yohinbine was injected 10 min before IP NS/propofol in the 4 groups. The visceral pain threshold was assessed by percentage of maximal possible antinociceptive effect （MPE） and was determined before IT administration （T0 ） and at 5, 10, 15, 20, 25, 30, 40, 60 min after IP NS/propofol. MPE = （pain threshold after drug administration - baseline pain threshold）/（80 mm Hg- baseline pain threshold）×100 % . Results MPE was significantly higher in group Ⅱ and Ⅳ than in group Ⅰ （P 〈 0.05 or 0.01）. MPE was significantly lower in group Ⅳ than in group Ⅱ （P 〈 0.01 ）. Conclusion Spinal cord α2-adrenoceptor activation is involved in the visceral antinociceptive effects of propofol in rats.
出处
《中华麻醉学杂志》
CAS
CSCD
北大核心
2008年第10期892-894,共3页
Chinese Journal of Anesthesiology
基金
江苏省自然科学研究基金资助项目（BK2005033）
江苏省卫生厅基金资助项目（K200518）
