Objective:To investigate the effect of hypoxia and reoxygenation on augmenter of liver regeneration expression and secretion in NRK52E cells

and conduct initial observation and analysis of exogenous rALR on p38 MAPK signal pathway.Methods: The cultured rat proximal tubular epithelial cell line(NRK52E cells)was divided into several groups

incubated in three gas incubators for different periods of hypoxia(2

4

8

12

18

24 h) and of reoxygenation(12

24 h)

or for various amounts of rALR.ALR mRNA levels were measured by semi-quantitative RT-PCR method;ALR protein expression were measured by Western blot.Hypoxia at different times(0

15

30

60 min)

and 15 min hypoxic cells in the control group

rALR group(20

100 μg of rALR) and SB203580 group

Western blot assayed p38MAPK protein expression cells.Results:(1) Normally cultured NRK52E cells had ALR mRNA expression.After hypoxia for 4 h

ALR mRNA expression was significantly increased compared with normal control(n=7

P<0.01);(2)Hypoxic cells being cultured for 12 h

cell ALR protein was significantly higher than that in the control group

and peaked in 18 h(n=7

P <0.01).(3)Hypoxia for 4 h

and reoxygenation for 12

24 h

ALR mRNA and protein expression increased significantly compared with the control group;(4)P38MAPK protein expression during hypoxia 15 min was the strongest;low-dose rALR(20 μg) significantly inhibited the activation of p38MAPK pathway

while the inhibition of high dose rALR(100 μg) decreased.Conclusion:Hypoxia and hypoxia/reperfusion can induce the expression of renal ALR.Low concentration and exogenous rALR can reduce the expression of p38MAPK pathway

which indicates that in hypoxia-reperfusion injury

ALR may have protective effects on rat renal tubular epithelial cell.