Dexmedetomidine reduces renal injury induced by lung ischemia/reperfusion in mice through inhibiting endoplasmic reticulum stress response / 中国病理生理杂志

ABSTRACT

AIM: To investigate the effect of dexmedetomidine (DEX) on renal injury induced by lung ischemia/reperfusion (I/R) in mice and its relationship with endoplasmic reticulum stress response.METHODS: Healthy SPF male C57BL/6J mice, weighing 20~24 g, aged 8~10 weeks, were randomly divided into 5 groups (n=10 each): sham operation group (sham group), I/R group, atipamezole (Atip) group, DEX group, and DEX+Atip group.In vivo lung I/R model was established by occlusion of the left pulmonary artery for 30 min followed by 180 min of reperfusion in the mice.The Atip (250 μg/kg), DEX (20 μg/kg) and DEX+Atip were intraperitoneally infused into the mice before left pulmonary hilus was blocked in Atip group, DEX group and DEX+Atip group, and other operations were the same as I/R group.After experiment, the mice were killed, and the renal tissues were harvested to observe the morphological changes.The enzymatic activity of caspase-3, serum creatinine and blood urea nitrogen, and cell apoptotic index of the renal cells were also analyzed.The expression of c-Jun N-terminal kinase (JNK), caspase-12, CCAAT/enhancer-binding protein homdogous protein (CHOP) and glucose-regulated protein 78 (GRP78) at mRNA and protein levels in the renal tissues was determined by RT-PCR and Western blot.RESULTS: Compared with sham group, the enzymatic activity of caspase-3, serum creatinine and blood urea nitrogen, renal cell apoptotic index, and the mRNA and protein levels of JNK, caspase-12, CHOP and GRP78 in I/R group were significantly increased (P<0.01), and the renal tissues had obvious damage under light microscope.Compared with I/R group, Atip group and DEX+Atip group, the enzymatic activity of caspase-3, serum creatinine and blood urea nitrogen, renal cell apoptotic index, and the mRNA and protein levels of JNK, caspase-12 and CHOP in DEX group were significantly decreased, and the expression level of GRP78 significantly increased (P<0.01).Furthermore, the renal tissue damage was obvious reduced.CONCLUSION: DEX effectively relieves the renal injury induced by lung I/R in mice, which may be associated with exciting α2-adrenergic receptor and inhibiting endoplasmic reticulum stress response.