安定-氯胺酮麻醉对烧伤小鼠早期炎症反应的影响

Effects of dlazepam-ketamine on inflammatory response during the early stage of burn in mice

目的研究安定-氯胺酮麻醉对烧伤小鼠腹腔巨噬细胞糖皮质激素受体(GR)及血清炎性细胞因子的影响,探讨其对创伤早期炎症反应的作用。方法120只BALB/C健康雄性小鼠随机分为正常对照组、烧伤对照组、麻醉对照组、先处理组(麻醉后15min烧伤)、后处理组(烧伤后15min麻醉)。采用安定-氯胺酮麻醉,小鼠烧伤模型为背部15%-20%Ⅲ度烧伤。于烧伤或麻醉后4h颈椎脱臼法处死小鼠,收集全血及腹腔巨噬细胞。采用ELISA法测定血清肿瘤坏死因子(TNF-α)、IL-1β、IL-10浓度,采用Westernblot技术测定腹腔巨噬细胞GR表达。取部分正常对照组和烧伤对照组腹腔巨噬细胞在体外与安定、氯胺酮共同培养,并测定腹腔巨噬细胞GR水平。结果与正常对照组比较,烧伤对照组血清TNF-α、IL-1β、IL-10浓度增高,先处理组血清IL-10浓度增高,后处理组血清IL-10浓度增高(P<0.01);与烧伤对照组比较,先处理组和后处理组血清TNF-α IL-1β、IL-10浓度降低(P<0.01或0.05)。与正常对照组比较,烧伤对照组、麻醉对照组和后处理组腹腔巨噬细胞GR表达水平降低(P<0.05或0.01);与烧伤对照组比较,先处理组和后处理组腹腔巨噬细胞GR表达水平明显增高(P<0.05或0.01);与先处理组比较,后处理组GR表达水平明显降低(P<0.05)。正常组或烧伤组腹腔巨细胞经安定.

Objective It has been shown that ketamine attenuates cytokine production and release induced by endotoxin. The purpose of this study was to investigate the effects of diazepam and ketamine on inflammatory responses during early stage of burn. Methods BALB/C male mice weighing 20-25 g were randomly divided into 5 groups : (1) normal control group (n = 10); (2) burn control group received Ⅲ degree bums covering 15%-20% of the body surface (n = 10); (3) D-K group received intramuscular diazepam 0.4mg·kg-1 and ketamine 10 mg·kg-1 ( n = 10); (4) D + K pretreatment group received D + K 15 min before burn ( n = 10) and (5) D + K post-treatment group received D + K 15 min after burn ( n = 10) . Four hours after burn or anesthesia (D + K) the animals were sacrificed and blood was collected for determination of serum TNF-α, IL-1β and IL-10 concentrations (ELISA) and peritoneal macrophages were isolated for detection of glucocorticoid receptor (GR) by Western blotting. In addition peritoneal macrophages isolated from normal animals (group 1) and bum animals (group 2) were cultured with diazepam-ketamine for 1 h befor detection of GR.Results Serum TNF-α, IL-1β and IL-10 levels in group 2 were significantly higher than those in group 1. In group 4 and 5 serum TNF-α, IL-lβ and IL-10 levels were significantly lower than those in group 2. In group 4 only serum IL-10 level whereas both serum IL-1β and IL-10 levels in group 5 were significantly higher than those in group 1. GR of peritoneal macrophage was significantly down regulated 4 h after bum (group 2) as compared with group 1. The level of GR in group 4 was significantly higher than that in group 2 but not significantly different from that in group 1; whereas the GR level in group 5 was significantly higher than that in group 2 but lower than that in group 1 and 4. There was no significant difference in GR expression after macrophages were cultured in vitro with diazepam and ketamine between normal or bum groups. Conclusion Diazepam-ketamine pretreatment can suppress cytokine release induced by severe bum. The expression of GR in peritoneal macrophages is significantly reduced by bum. Diazepam-ketamine given before or after bum can suppress the inflammatory response but have no direct effect on peritoneal macrophages.