Role And Mechanism Of Peripheral-type Benzodiazepine Receptor In Human Renal Tubular Cells Injury Induced By Postasphyxial-Serum Of Neonates

Objective To investigate the role and mechanism of peripheral-type benzodiazepine receptor in human renal tubular cells induced by postasphyxial-serum of neonates.Methods (1) Human renal proximal tubular cell line (HK-2 cells) were used as target cell. (2)The serum of neonates in one day after asphyxia(Apgar Scoring less than 4), whose concentration were 20%(volume fraction),were applied as attacking factor. (3) The experiment was designed as control group(Group C), asphyxia group(Group AC), the group of pretreatment with Ro5-4864(Group AR), the group of pretreatment with PK11195(Group AP). (4) The following indicators were detectied:The changes of morphology were observed under inverted microscope. The expression of caspase-9, Bax and Bcl-2 in cytoplast were detected by the use of immunohistochemical method. (5)A11 parameters were expressed as the mean value±standard difference(x±S), statistical analysis were carried out by the use of one-way ANOVA. Between two groups, which were carried out by the use of the least significant difference. Difference was considered significance when the p.value was less than 0.05. The statistics work were finished by spss10.0 software.Results (1)Under inverted microscopy, HK-2 cells in control group were significantly increased, sticked to each other tightly and grew very quickly. Their adhesion were better, multy-ang applan, and refraction raised. The form and quantity of HK-2 cell was normal. Compared with control group, the changes in morphology of HK-2 were most serious and obvious in asphyxia group, the cells grew slowly, the mount decreased, form of the cells changed from typical multy-ang applan to off-normal round or ellipse. Refraction rate was decreased, and contour enhanced. The vacuolus, lipid droplet and granulation appeared in the kytoplasm. There was much cell debris in accrescent intercellular space. Compared with the group of HK-2 with postasphyxial-serum, the shape of the cells is better in the group with Ro5-4864, the but it is worse than that of the control group. And the shape of the cells HK-2 who was treated with PK11195 is worse compared with the group of postasphyxial-serum. (2)Expression of caspase-9 and the Bax. Compared with controls group(32.11±5.12,23.55±3.86),the expression of caspase-9(63.58±3.80) and Bax(53.23±2.89) were significantly increased in asphyxia group. But compared with asphyxia group, the expression of caspase-9(48.59±5.91) and Bax(41.52±3.65) were significantly decreased in the group of pretreatment with Ro5-4864. However the expression of caspase-9(75.34±4.83) and Bax(60.28±2.97) were significantly increased in the group of pretreatment with PK11195(P<0.05). (3) Expression of Bcl-2. Compared with controls group(70.36±6.02),the expression of Bcl-2(46.29±4.98) were significantly increased in asphyxia group. But compared with asphyxia group, the expression of Bcl-2(60.45±5.26) were significantly increased in the group of pretreatment with Ro5-4864. And a increased in the group of pretreatment with PK11195 in the expression of Bcl-2(28.37±4.05)(P＜0.05).Conclusion Ro5-4864 which is the agonist of the PBR could relieve the apoptosis of human renal tubular cells induced by postasphyxial-serum in neonates. However PK11195,which is the antagonist of the PBR,could result in the destruction of HK-2, even worse. The both reaction may occur by relieve or active the PBR.