肾上腺髓质素在大鼠肾缺血再灌注损伤中的作用研究

目的：探讨肾上腺髓质素（ADM）对大鼠肾缺血再灌注（IR）损伤的作用，并对其可能的机制进行初步研究。方法：采用右肾切除。左肾肾动脉夹闭50min/再灌注24h的动物模型，将40只雄性Wistar大鼠随机分为假手术组（n=8)，肾IR组（n=8)，ADM预防组（n=24，组内又按给药剂量不同分为0．05nmol/kg ADM组，0．1nmol/kg ADM组和1．0nmol/kg ADM组，每组n=8)，观察肾组织中丙二醛（MDA）含量，总抗氧化能力（TAOC）和总超氧化物歧化酶（T－SOD），Mn-SOD,Cu-Zn-SOD活力和血肌酐（Cr)，尿素氮（BUN）含量以及组织形态学改变。结果：与假手术组相比，肾IR组MDA，Cr和BUN升高，组织学损伤较重，TAOC，T－SOD，Mn-SOD和Cu-Zn-SOD活力下降（P＜0．01），肾IR前给予ADM则量依赖性逆转了上述病理改变（P＜0．05），结论：ADM可能经提高内源性抗氧化能力，尤其是SODI知力减轻肾IR。

STUDIES ON THE ROLE OF ADRENOMEDULLIN IN ISCHEMIA-REPERFUSION INJURY OF RAT KIDNEY

Objective:To investigate the role of adrenomedullin(ADM) in rats inflicted to renal ischemia reperfusion(IR) injury and study its mechanism as well as significance in the pathogesis process of renal IR injury. Methods:In a fight-nephrectemized ,50 minutes interruption of left renal artery blood flow and then 24h ours of reperfusion rat model,40 wistar rats were divided into three group:sham operration group,renal IR group, ADM pretreatment group(this group was divided into three small group ,that is 0.05,0.1,1.0 nmol/kg ADM group). we observed serum levels of creatinine(Cr) and blood urea nitrogen(BUN),histopathological damages and tissue malondialdehyde (MDA) contents as well as total superoxide dismutese(T-SOD),Mn-SOD, Cu-Zn-SOD activity and total anti-oxidative capability(TAOC).Result:compared with sham operation group, renal cellular damages showed more severe and MDA content and the serum levels of Cr and BUN were higher, but TAOC and SOD activity decreased (P< 0.01) in renal IR group (P<0.01);Administration of ADM before renal ischemia caused a dose related reduction in BUN,Cr, MDA content and less cellular damages(P< 0.05) and increased the levels of TAOC and SOD activity in a dose-dependent manner compared with renal IR group(P< 0.05).Conclusion:ADM pretreatment may induce renal protection against rats' renal IR injury through activating endogenous anti-oxidative capability, especially SOD activities.