RENAL LITHOSTATHINE, A NEW INHIBITOR OF U RINARY STONES FORMATION

Lithostathine is a protein of pancreatic secretion inhibiting calcium carbonate crystal growth Antibodies to lithostathine were used to iden tify a related protein in urine and kidney stones. Western blot analys is of proteins extracted from concentrated normal urine or kidney ston es demonstrated the presence of a protein with an apparent molecular w eight of 23 kDa. The same antibodies were used in immunolocalization e xperiments on fresh human nephrectomy specimens cryosections. A positi ve signal was observed in the cells of proximal tubules and thick asce nding limbs of Henle's loop. Protein extracts of renal stones inhibite d calcium carbonate crystal growth. Because of its structural and func tional similarities with pancreatic lithostathine, it was called renal lithostathine.