精氨酸对老年大鼠受压组织的炎症反应及氧化损伤的干预作用

Intervention Effect of L-Arg on Inflammable Response and Oxidative Damage in Elderly Rats Submitted to Stage I Pressure Ulcer

目的探讨L-精氨酸(L-arginine,L-Arg)对老年Ⅰ期压疮大鼠受压组织一氧化氮(nitric oxide,NO)、一氧化氮合酶(nitric oxide synthase,NOS)、白细胞介素-6(interleukin 6,IL-6)及超氧化物歧化酶(super oxide dismutase,SOD)的影响,为老年压疮的防治提供实证依据。方法随机将20只老年SD大鼠分成三组,对照组和模型组各6只,采取普通饲料喂养20 d。L-Arg干预组8只,给予普通饲料加2.6 g/(kg·d)的L-Arg灌胃喂养20 d。对照组不受压、模型组和L-Arg干预组承受22.47 kPa压力2 h后3组大鼠一起实施安乐死。采集受压组织中心标本,常规石蜡切片、苏木精-伊红染色;光镜下观察3组大鼠皮肤肌肉组织病理学变化;检测10%匀浆肌组织中NO、NOS、IL-6及SOD的含量和活性。结果受压组织病理形态学显示,与模型组相比,L-Arg干预组受压表皮与组织炎症细胞浸润较模型组减少,受压组织受损程度明显减轻(P<0.01);与正常组相比,模型组NO、NOS及IL-6明显升高(P<0.01);SOD显著降低(P<0.01)。与模型组相比,L-Arg干预组NO、NOS及IL-6明显降低(P<0.01);SOD增高(P<0.05)。结论小剂量LArg的早期干预可有效抑制受压组织的过氧化反应及炎症细胞浸润,从而降低老年大鼠压疮发生率。

Objective To study the effects of L-arginine （L-Arg） on the contents and the activity of nitric oxide （NO） ,nitric oxide synthase（NOS）, superoxide dismutas （SOD） and interleukin 6 （IL-6） in tissues of elderly rats with first stage pressure sore and provide empirical evidence for prevention of pressure sore in elderly patients. Method A to- tal of 20 elderly SD rats were divided into control group （n = 6） ,model group （n = 6） and experimental group （n = 8） . The rats in the control group and model group were fed by a normal diet while the experimental group were fed by a nor- mal diet mixed with an gauage feeding with L-Arg [-2.6 g/（kg·d）] for 20 days. The rats in the control group were given no pressure while the model group and the experimental group were given 22.47 kPa pressure for 2 hours. All rats were given euthanasia afterwards and the tissue specimens were collected to make paraffin sections, HE stains and fluorescent TUNEL markers. The pathological change of the skin tissues were observed under the light microscope and the content as well as the activity of NO, NOS IL-6 and SOD were measured.Results The pathological morphology indicated that both the saturation and the tissue damage were alleviated, and the number of inflammable cells were reduced in the experimen- tal group （P〈0.01） compared to the model group.The content and the activity of NO, NOS and IL-6 of rats in the model group was significantly higher than that in the control group （P〈0.01） but significantly lower than that in the experi- mental group （P〈0.01）.The content and the activity of SOD of rats in the model group was significantly lower than that in the control group （P〈0.01） but significantly higher than that in the experimental group （P〈0.05） .Conclusion Early eternal feeding with low dose L-Arg can effectively inhibit super oxidation and inflammable reaction with potential in re- ducing the morbidity of pressure sore in elderly patients.