ATRIAL-NATRIURETIC-PEPTIDE INHIBITS MESANGIAL CELL-PROLIFERATION INDUCED BY EARLY POSTNEPHRECTOMY SERUM

Rat kidney mesangial or tubular cells were grown in tissue culture med ium supplemented with sera of 20 sham-operated vs. 20 nephrectomized C harles River rats. Each cell sample was grown with or without addition of atrial natriuretic peptide (ANP) to the medium. ANP completely abo lished the growth stimulatory effect of postnephrectomy serum [i. e., effect of renotropic factor(s) present in the serum] on mesangium cell s. Tubular cell proliferation was unchanged We propose that interactio n between renotropin and atrial natriutetic peptide activity might be one of the possible mechanisms regulating compensatory renal growth fo llowing nephrectomy.