Lin Ji, Yan Guang-tao, Gao Xiao-ning, Liao Jie, Hao Xiu-hua, Zhang Kai
Research Laboratory of Biochemistry, General Hospital of PLA, Beijing 100853, China.
Nan Fang Yi Ke Da Xue Xue Bao. 2006 Jun;26(6):719-24.
To explore the effect of intestinal ischemia/reperfusion (I/R) injury on leptin and orexin-A levels in peripheral blood and central secretory tissues, and investigate the roles of leptin and orexin-A in acute inflammatory responses.
An intestinal I/R injury rat model was established, and the rats were grouped according to duration of the reperfusion time following a 60-min ischemia. Radioimmunoassay was used to examine the protein levels of leptin in the serum and adipose tissue, and the protein levels of orexin-A in the plasma and hypothalamus. Reverse transcriptase-polymerase chain reaction was also performed to detect the mRNA expressions of adipose leptin and hypothalamus orexin-A.
Compared with that before injury, serum leptin level of 60-min ischemia with 30-min reperfusion (I60'R30') group decreased significantly and that of I60'R360' increased significantly. Compared with the sham-operation group (sham) after injury, serum leptin level of I60'R360' group increased significantly, and adipose leptin protein levels of I60'R30' and I60'R90' groups decreased significantly, whereas that of I60'R360' group increased obviously. Compared with sham group after injury, adipose leptin mRNA expressions of I60'R30', I60'R240' and I60'R360' groups all increased significantly, while that of I60'R150' showed significant decrease. No significant changes were noted in the protein levels of orexin-A either in the plasma or hypothalamus after I/R injury. In comparison with sham group after injury, hypothalamus orexin-A mRNA expressions of I60'R30' and I60'R90' groups showed gradual but significant decrease, and till 150 min of reperfusion, the expression reached its lowest, followed then by slow recovery at 240 and 360 min, though still remaining significantly lower than that of sham group.
Leptin and orexin-A have a time-dependent response to intestinal I/R injury, but the former appears to exhibit a faster response, and they may play a certain role in the metabolic disorders of acute inflammation.
探讨肠道缺血/再灌注（I/R）损伤对外周血及中枢分泌组织中瘦素和食欲素A水平的影响，并研究瘦素和食欲素A在急性炎症反应中的作用。
建立肠道I/R损伤大鼠模型，根据缺血60分钟后的再灌注时间对大鼠进行分组。采用放射免疫分析法检测血清和脂肪组织中瘦素的蛋白水平，以及血浆和下丘脑食欲素A的蛋白水平。还进行逆转录聚合酶链反应检测脂肪组织瘦素和下丘脑食欲素A的mRNA表达。
与损伤前相比，缺血60分钟再灌注30分钟（I60'R30'）组血清瘦素水平显著降低，而I60'R360'组显著升高。与损伤后的假手术组（sham）相比，I60'R360'组血清瘦素水平显著升高，I60'R30'和I60'R90'组脂肪组织瘦素蛋白水平显著降低，而I60'R360'组明显升高。与损伤后的假手术组相比，I60'R30'、I60'R240'和I60'R360'组脂肪组织瘦素mRNA表达均显著升高，而I60'R150'组显著降低。I/R损伤后血浆或下丘脑食欲素A的蛋白水平无显著变化。与损伤后的假手术组相比，I60'R30'和I60'R90'组下丘脑食欲素A mRNA表达呈逐渐但显著下降，至再灌注150分钟时，表达降至最低，随后在240分钟和360分钟缓慢恢复，但仍显著低于假手术组。
瘦素和食欲素A对肠道I/R损伤具有时间依赖性反应，但前者反应似乎更快，它们可能在急性炎症的代谢紊乱中发挥一定作用。
