热休克蛋白70减轻大鼠急性坏死性胰腺炎机制的实验研究

目的 探讨热休克蛋白70减轻大鼠急性坏死性胰腺炎的机制.方法 80只SD大鼠随机分为4组,急性坏死性胰腺炎模型组（A）、假手术组（B）、温生理盐水腹腔灌洗预处理后急性坏死性胰腺炎（ANP）组（C）和温生理盐水腹腔灌洗和丝裂原活化蛋白激酶p38（p38MAPK）抑制剂（SB202190）预处理后ANP组（D）,ANP模型由5%牛黄胆酸钠大鼠胰胆管逆行注射诱发而成.C组使用温生理盐水持续腹腔灌洗30 min,10 h后造ANP模型;D组在使用温生理盐水腹腔冲洗后,立刻行SB202190（10 mg/kg）腹腔注射,10 h后制造ANP模型.ANP术后6 h处死大鼠,检查各组大鼠血清细胞因子IL-6、TNF-α和IL-8;血清淀粉酶;取胰腺组织行病理检查,并使用PCR方法检测胰腺中热休克蛋白70（HSP70）/p38-MAPK的表达.结果 SB202190预处理组大鼠血清淀粉酶[（1779.77±84.90）U/L]和温生理盐水腹腔灌洗预处理组[（2845.70＆#177;204.78）U/L]明显低于ANP组[（4064.93±188.97）U/L,P＜0.05],但高于假手术组[（1221.47±54.58）U/L,P＜0.05];SB202190预处理组低于温生理盐水腹腔灌洗预处理组（t＝3.329,P＜0.05）.SB202190预处理组和温生理盐水腹腔灌洗预处理组大鼠血清TNF-α、IL-6、IL-8明显低于ANP组（P＜0.05）,但高于假手术组（P＜0.05）;SB202190预处理组低于温生理盐水腹腔灌洗预处理组（P＜0.05）.SB202190预处理组和温生理盐水腹腔灌洗预处理组胰腺组织p38MAPK mRNA含量明显低于ANP组（P＜0.05）,温生理盐水腹腔灌洗预处理组高于假手术组（P＜0.05）;SB202190预处理组低于温生理盐水腹腔灌洗预处理组（P＜0.05）.结论 HSP70可以通过调控p38MAPK从而下调细胞因子的表达,进而改善大鼠ANP病理生理.

Experimental study on the mechanism of the HSP70 in reducing acute necrotizing pancreatitis of rats

Objective To explore the mechanism of heat shock protein 70 （HSP70） in reducing acute necrotizing pancreatitis （ANP）. Methods A total of 80 Sprague-Dawley （SD） rats was randomly divided into group A （ acute necrotizing pancreatitis）, group B （sham-operated）, group C （warm saline pretreatment ANP）, and group D [ warm saline and mitogen-activated protein kinase （p38MAPK） inhibitor（SB202190） pretreatment ANP], with 20 rats in each group. ANP model was induced by retrograde injection of 5% sodium tauroeholate to rat pancreatic duct. Group C using physiological saline celiac lavage for 30 minutes, ANP model was made after 10 hours. In group D, after physiological saline celiac lavage, SB202190 （10 mg/kg） was given by intraperitoneal injection, and made ANP after 10 hours. The rats were sacrificed at the 6th hours after ANP operation. Serum levels of tumor necrosis factor-~, Inter- leukin-6 （IL-6）, IL-8, and amylase were measured by enzyme-linked immunosorbent assay （ELISA）. The pancreas tissues were ob- tained to examine the change with microscope, the expressions of HSP70 and p38MAPK were examined by polymerase chain reaction （PCR） method. Results The level of serum amylase in group C[ （2845.70 ±204. 78）U/L]was significantly lower than in group A, but higher than that in group B[ （ 1221.47 ±54. 58）U/L] and group D [ （1779. 77 ±84. 90）U/L] （ P 〈 0. 05 ）. The level of serum TNF-α, IL-6 and IL-8 in the peritoneal lavage group were lower than the ANP group but were higher than the sham-operated group and the SB202190 pre-management group （ P 〈0. 05）. In group C, the level of p38MAPK lower than that in ANP group （ P 〈0.05）. The level of p38MAPK mRNA in peritoneal lavage pretreated group was significantly lower than the ANP group , but higher than the sham group and SB202190 pretreatment group （ P 〈 0. 05 ）. Pancreatic pathological damages were much milder in groups D and C than those in group A under microscope. Conclusions Through down-regulating the expression of p38MAPK, HSP70 decreases in- flammatory mediator levels, and reduces the pathophysiology damage of the ANP.