Growth inhibitory activity of atrial natriuretic factor in rat glomerular mesangial cells

Atrial natriuretic factor (ANF) binding sites, or ANF-induced cGMP accumulation, have been shown in numerous tissues that may not be intimately involved in volume homeostasis. In a series of experiments, we found that quiescent rat glomerular mesangial cells in culture could be reactivated to enter the cell cycle, and that ANF had potent inhibitory effects on proliferation of these cells. [3H]Thymidine incorporation increased by fivefold in reactivated compared to quiescent cells, and ANF in physiologic concentrations inhibited this incorporation by 48%. Thus, ANF appears to be a multifunctional peptide, consistent with a number of peptide growth factors.