High expression of type I inositol 1,4,5-trisphosphate receptor in the kidney of rats with hepatorenal syndrome

AIM To detect the expression of typeⅠ inositol 1,4,5-trisphosphate receptor(IP3 RI) in the kidney of rats with hepatorenal syndrome(HRS).METHODS One hundred and twenty-five Sprague-Dawley rats were randomly divided into four groups to receive an intravenous injection of D-galactosamine(D-Gal N) plus lipopolysaccharide(LPS; group G/L, n = 50), D-Gal N alone(group G, n = 25), LPS alone(group L, n = 25), and normal saline(group NS, n = 25), respectively.At 3, 6, 9, 12, and 24 h after injection, blood, liver, and kidney samples were collected. Hematoxylineosin staining of liver tissue was performed to assess hepatocyte necrosis. Electron microscopy was used to observe ultrastructural changes in the kidney. Western blot analysis and real-time PCR were performed to detect the expression of IP3 RI protein and m RNA in the kidney, respectively.RESULTS Hepatocyte necrosis was aggravated gradually, which was most significant at 12 h after treatment with D-galactosamine/lipopolysaccharide, and was characterized by massive hepatocyte necrosis. At the same time, serum levels of biochemical indicators including liver and kidney function indexes were all significantly changed. The structure of the renal glomerulus and tubules was normal at all time points. Western blot analysis indicated that IP3 RI protein expression began to rise at 3 h(P < 0.05) and peaked at 12 h(P < 0.01). Real-time PCR demonstrated that IP3 RI m RNA expression began to rise at 3 h(P < 0.05) and peaked at 9 h(P < 0.01).CONCLUSION IP3 RI protein expression is increased in the kidney of HRS rats, and may be regulated at the transcriptional level.