右美托咪定或(和)舒芬太尼预处理对浸水束缚应激大鼠急性胃黏膜损害的影响

摘要

目的:探讨右美托咪定(DEX)预处理或(和)舒芬太尼(SUF)预处理对浸水束缚应激(WIRS)大鼠急性胃黏膜损害的影响.方法:30只Wistar大鼠随机分成正常对照组(NC组,n=6)、WIRS对照组(WC组,n=6)、DEX预处理组(DP组,n=6)、SUF预处理组(SP组,n=6)、DEX复合SUF预处理组(DSP组,n=6).DP组:腹腔注射7.5 μg/kg 10 min后进行WIRS; SP组:腹腔注射10 μg/kg2 min后进行WIRS;DSP组:腹腔注射7.5 μg/kg DEX 8 min后再注射SUF 10 μg/kg,2 min后进行WIRS；以等容积生理盐水腹腔注射后10 min进行WIRS作为WC组.所有实验大鼠于WIRS 6 h后给予10％水合氯醛3 mL/kg腹腔注射麻醉,剖腹取出全胃后先进行胃液pH测定、胃黏膜损伤指数(GI)评定,然后按要求留取胃黏膜组织标本以检测胃黏膜组织超氧化物歧化酶(SOD)、丙二醛(MDA)、髓过氧化物酶(MPO)和一氧化氮合酶(NOS)的含量和病理学检查.结果:DEX预处理后,MDA、MPO升高幅度都较WC组明显降低,pH、SOD下降幅度明显减少,GI和胃黏膜损伤病理改变较WC组减轻(P＜ 0.05),但NOS的变化没有统计学意义(P＞0.05)；与SP组比较,DSP组SOD、MDA、GI、pH、MPO、NOS的变化无统计学意义(P＞0.05).结论:DEX预处理可有效减轻WIRS诱发的急性胃黏膜损伤,其确切机制尚不清楚,可能与控制伤害性应激反应、降低氧化应激、降低胃酸和抑制炎症反应有关,但并没有使舒芬太尼对胃黏膜损伤的保护作用增强.%Objectives To explore the effects of dexmedetomidine on sufentanil pretreatment rats with acute gastric mucosal lesions induced by water-immersion-restraint stress. Methods Thirty wistar rats were randomly assigned to normal control group (Group NC, n = 6); WIRS controlled group (Group WC, n = 6, intraperitoneal infusion of saline 10 min before WIRS); DEX pretreatment group (Group DP, n = 6, intraperitoneal infusion of dexmedetomidine at 7.5 μg/kg 10 min before WIRS); SF pretreatment group (Group SP, n = 6, intraperitoneal infusion of sufentanil at 10 μg/kg 2 min before WIRS); DEX and SF pretreatment group (Group DSP, n = 6, intraperitoneal infusion of dexmedetomidine at 7.5 μg/kg 10 min and intraperitoneal infusion of sufentanil at 10 μg/ kg 2 min before WIRS). All rats were anesthetized by intraperitioneal injection of 10% chloral hydrate 6h after WIRS.Then the whole stomach was removed and the gastric pH, SOD, MDA, MPO and NOS levels were measured. The gastric mucosal lesion index (GI) was assessed and gastric mucosal tissues underwent pathological examination. Results The increased range of MDA and MPO, the decreased range of pH and SOD, GI and pathological changes of gastric mucosal damage in the DP group were significantly lower than those in the WC group (P 〈 0.05), but the change of NOS was not statistically significance (P〉0.05). Compared with the SP group, the various of SOD, MDA, UI, pH, MPO, NOS in DSP group have no significant change (P 〉 0.05). Conclusions Dexmedetomidine pretreatment can effectively reduce the stress-induced acute gastric mucosal injury, and the mechanism may be related to control harmful stress response,reduce oxidative stress, reduce gastric acid and inhibit the inflammatory response, but it did not enhance the protective effect of sufentanil on acute gastric mucosal injury.