Expressions of CaSR and Claudin-14 in Renal Calcium Oxalate Stone Model of Rats / 天津医药

ABSTRACT

Objective To investigate the expressions of calcium sensitive receptor (CaSR) and tight junction protein (Claudin)-14 in renal calcium oxalate stone rat model. Methods Thirty male SD rats were randomly divided into control group (n=15) and model group (n=15). The rat model of renal calcium oxalate stone was established by gavaging 1%glycol (2 mL/d) and 2% ammonium chloride. The expression of CaSR protein was detected using immunohistochemical assay. RT-PCR was used to detect the Claudin-14 mRNA expression. The expression levels of CaSR and Claudin-14 protein were de-tected by Western blot assay respectively. The full automatic biochemical analyzer was used to detect rat renal function and changes of blood and urine biochemical indices. Results A large stone crystallization was observed under light microscope in model group. The serum levels of Cr, BUN, 24-h urine calcium and urine volume were significantly higher in model group than those of control group (P<0.01). There were no significant differences in serum calcium level and urinary pH value be-tween two groups. The expression levels of Claudin-14 mRNA and CaSR protein were significantly higher in model group than those of control group (P<0.01). The Claudin-14 protein expression was specifically higher in renal tissues of model group. There was no Claudin-14 protein expression in control group. There was a positive correlation between CaSR and Claudin-14 protein expression in renal tissues of model group. Also, CaSR and Claudin-14 protein expressions were posi-tively correlated with the 24-h urine volume. Conclusion The increased expressions of CaSR and Claudin-14 involved in the formation of kidney stone by increasing the urinary calcium excretion.