摘要
背景:七氟醚与丙泊酚具有镇痛的作用,还可通过抑制神经细胞凋亡发挥神经保护作用,但具体作用机制尚未完全了解。目的:研究七氟醚复合丙泊酚对脊髓骨折大鼠疼痛递质、神经细胞活性及丝裂原活化蛋白激酶(mitogen activated protein kinase,MAPK)/环磷酸腺苷反应元件结合蛋白(cAMP response element binding peotein,CREB)的影响。方法:80只SPF级SD雄性大鼠随机抽取15只作为健康组进行对照,剩余大鼠建立脊髓骨折模型,建模中意外死亡5只,60只建模成功大鼠随机分为模型组、七氟醚组、丙泊酚组以及联合组,每组15只。七氟醚组大鼠置于密闭实验箱中,给予氧流量2 L/min,吸入2%七氟醚0.5h;丙泊酚组大鼠于尾静脉泵注2mL/(kg·h)丙泊酚4h;联合组大鼠在七氟醚组的基础上给予丙泊酚干预;健康组与模型组大鼠吸入纯氧0.5 h。在治疗后1 d及1,2,3周,采用von Frey细丝法测定大鼠机械缩足反射阈值(MWT)变化,苏木精-伊红染色观察脊髓组织病理形态;TUNEL检测脊髓组织中神经元细胞凋亡情况;Real Time-PCR检测脊髓组织p38MAPK、CREB基因表达;免疫印迹检测脊髓组织p38MAPK,CREB,p-p38MAPK及p75NTR蛋白的表达。结果与结论:(1)与健康组相比,其他4组大鼠各时间点机械缩足反射阈值降低(P<0.05);与模型组相比,各时间点七氟醚组、丙泊酚组与联合组机械缩足反射阈值升高(P<0.05),其中联合组最高(P<0.05);(2)模型组白质与中央灰质融合成极大空腔,白质有大量大空泡;七氟醚组与丙泊酚组白质与中央灰质有大量裂隙,白质有大量小空泡;联合组白质与中央灰质少量裂隙,白质可见少量小空泡;(3)模型组神经元细胞凋亡数量高于七氟醚组、丙泊酚组与联合组(P<0.05);联合组神经元细胞凋亡数量最低(P<0.05);(4)与健康组相比,其他4组大鼠p38MAPK、CREB mRNA和蛋白表达及p-p38MAPK蛋白表达增加(P<0.05),p75NTR蛋白水平降低(P<0.05);与模型组相比,七氟醚组、丙泊酚组与联合组大鼠p38MAPK mRNA和蛋白表达及p-p38MAPK蛋白表达降低,CREB mRNA和蛋白及p75NTR蛋白表达升高(P<0.05);联合组大鼠上述mRNA和蛋白的表达变化最显著(P<0.05);(5)结果提示:七氟醚复合丙泊酚可有效改善脊髓骨折大鼠神经病理性疼痛,并抑制神经元细胞凋亡,发挥治疗脊髓骨折作用,这可能与抑制p38MAPK表达、促进CREB表达有关。
BACKGROUND:Both sevoflurane and propofol have analgesic effects and exert neuroprotective effects by inhibiting neuronal apoptosis,but the specific mechanisms are not fully understood.OBJECTIVE:To study the effects of sevoflurane combined with propofol on pain mediators,nerve cell activity and mitogen activated protein kinase(MAPK)/cAMP response element binding peotein(CREB)in rats with spinal cord fracture.METHODS:Of 80 SPF male Sprague-Dawley rats,15 rats were randomly selected as healthy group and the remaining rats were used to make animal models of spinal cord fracture.During the modeling,five rats were dead unexpectedly.After successful modeling,60 model rats were randomized into model group,sevoflurane group,propofol group,and combined group(sevoflurane+propofol),with 15 rats in each group.The rats in the sevoflurane group were placed in a closed experimental box,given an oxygen flow of 2 L/min,and inhaled 2%sevoflurane for 0.5 hours;the rats in the propofol group were injected with 2 mL/kg/h propofol through the tail vein for 4 hours;the rats in the combined group were given both propofol and sevoflurane interventions;and the rats in the healthy group and model group inhaled pure oxygen for 0.5 hours.Von Frey filament method was used to measure mechanical withdrawal threshold values.Hematoxylin-eosin staining was used to observe the pathological morphology of spinal cord tissue of rats.TUNEL was used to detect the apoptosis of neurons in spinal cord tissue of rats.Real-time PCR was used to detect the expression of p38MAPK and CREB mRNA.Western blot assay was used to detect the expression of p38MAPK,CREB,p-p38MAPK,and p75NTR proteins in spinal cord tissue of rats.RESULTS AND CONCLUSION:(1)Compared with the healthy group,the mechanical withdrawal threshold value was decreased in the other four groups at different time points(P<0.05).Compared with the model group,the mechanical withdrawal threshold value was significantly increased in the sevoflurane,propofol,and combined groups at different time points(P<0.05),especially in the combined group(P<0.05).(2)In the model group,the white matter and central gray matter fused into a large cavity,and the white matter had a large number of vacuoles.In the sevoflurane and propofol groups,there were many cracks in the white matter and central gray matter and massive small vacuoles in the white matter.In the combined group,there were a few cracks in the white matter and central gray matter and a few vacuoles in the white matter.(3)The apoptosis rate of neurons in the model group was significantly higher than that in the sevoflurane,propofol,and combined groups(P<0.05).The apoptosis rate of neurons was lowest in the combined group(P<0.05).(4)Compared with the healthy group,the mRNA and protein levels of p38MAPK and CREB were significantly increased in the other four groups(P<0.05),while the expression of p75NTR was significantly decreased(P<0.05).Compared with the model group,the expression of p38MAPK mRNA and protein as well as the expression of p-p38MAPK protein decreased in the sevoflurane,propofol,and combined groups,while the expression of CREB mRNA and protein and the expression of p75NTR protein increased(P<0.05).Changes in the expression of above mRNAs and proteins were most significant in the combined group(P<0.05).(5)To conclude,sevoflurane combined with propofol can effectively improve neuropathic pain and inhibit neuronal apoptosis in rats with spinal cord fracture,which may be related to inhibiting the expression of p38MAPK and promoting the expression of CREB.
作者
郭永娟
张丽
陆化梅
Guo Yongjuan;Zhang Li;Lu Huamei(Department of Anesthesia and Perioperative Medicine,Luoyang Orthopedic-Traumatological Hospital of Henan Province(Henan Provincial Orthopedic Hospital),Luoyang 471000,Henan Province,China;Clinical Pharmacokinetics Research Department,Luoyang Orthopedic-Traumatological Hospital of Henan Province(Henan Provincial Orthopedic Hospital),Luoyang 471000,Henan Province,China)
出处
《中国组织工程研究》
CAS
北大核心
2023年第36期5850-5855,共6页
Chinese Journal of Tissue Engineering Research
基金
河南省中医药科学研究专项课题(2019ZY2090),项目负责人:张丽。
