The Significant Of Calcium Sensing Receptor Expression In Renal Tissue Of Nephrotic Syndrome With Mild Mesangial Proliferative Glomerulonephris

Objective:To investigate expression of Calcium-sensing receptor (CaSR) in renal tissue of mild mesangial proliferative glomerulonephris (mild-MsPGN), that was primary nephrotic syndrome(PNS) in clinical symptom, for further understanding relationship between CaSR and nephric tubule injury. Method:30 PNS patients who were clinically diagnosed PNS and final diagnosis mild-MsPGN by renal needle biopsy from 2005 to 2009. Patients are divide into two group base on estimation glomerular filtration rate (eGFR). The eGFR was calculated by using modified MDRD formula. The eGFR of normal renal function (NRF) group was more than 90ml/min, but renal function disfuction (RD) group was little than 90ml/min. Every group has 15 patients. Clinical data including blood calcium, serum albumin, blood urea nitrogen (BUN), serum creatinine (Crea) and twenty-four-hour urine protein quantitation were collected. Renal tissue was stained by periodic acid-schiff and immunohistochemistry. Pathological change was observed under microscope. Degree of Tubulointerstitial damage (TID) were carry out semiquantitative score. Expression of CaSR were semiquantitatively analyzed by image analysis. Result: The level of BUN and Cre were obviously increased in NRF group than in RD group (P＜0.05). The eGFR were lower in RD group than in NRF. There are differentiation on degree of renal tubulointerstitial damage in NRF and RD groups by histopathologic examination. Different intensity of CasR were expressed in renal tissue. CaSR mainly expressed in enal tubular epithelial cell, now and then in renal glomeruli. Expression of CaSR was significantly decreased in RD group compared with NRF group. And distribution of CaSR was unevenness and unexpression in same one renal tubule. Between integral optical density value and TID were negative correlation (r=0.40, P<0.05). TID was more bigger, IOD was more less. Conclusions:These results indicated that CaSR expressed in renal tissue of nephrotic syndrome with mild mesangial proliferative glomerulonephris, especially in nephric tubule. CaSR expression was reduced when TID was severe, and also suggested that downregulation of CaSR expression may be participate nephric tubule injury of MsPGN patient.