Novel roles of cardiac natriuretic peptides in renal compensatory hypertrophy

Abstract

Background Loss of renal tissue and renal function results in an increase in function and mass of the remaining intact kidney tissue. A prominent example for this so called renal compensatory hypertrophy is the removal of one kidney (uninephrectomy, UNx) for instance in living kidney donors. Although it is well established that kidney size and function of the remaining kidney markedly increase in these patients and that these adaptations are a prerequisite for living kidney donation, several open questions regarding the regulation of the compensatory mechanisms remain. For instance the initial signals inducing the increase in glomerular filtration rate (GFR) are largely unknown. Based on previous studies demonstrating that I. the rapid increase in GFR post-UNx is mediated by a circulating factor and II. the cardiac natriuretic peptides ANP and BNP both are capable of increasing the GFR, we speculated that natriuretic peptides might be the long sought factor mediating the functional adaptation of kidney function in response to a loss of kidney tissue.