Introduction 1 2 3 4 Localization in the kidney 3 4 5 5 6 Possible upregulation of (pro)renin receptor expression under hypertensive conditions 7 8 9 Effects of (pro)renin receptor overexpression on the kidney 10 1 11 12 Fig. 1 h(P)RR  Receptor-bound prorenin in diabetic kidneys 13 14 15 16 17 18 17 15 Receptor-bound prorenin in hypertensive kidneys 19 7 9 20 21 22 Possible inhibition of receptor-bound prorenin by high levels of renin 2 3 23 23 16 18 15 7 24 22 Fig. 2 Renin and prorenin competitively bind to the (pro)renin receptor in vivo and to the (pro)renin receptor expressed on the cell surfaces of COS-7 cells  (Pro)renin receptors in cultured cells 25 21 1 13 25 8 8 3 Fig. 3 Possible fragmentation of (pro)renin receptor in cultured cells  25 26 4 20 27 8 3 Conclusion In the glomerulus of the kidneys, the (pro)renin receptor is not only present in the mesangium but is also abundant in the podocytes and its expression was increased by two- to threefold in the kidneys of some animal models of hypertension. A transgene-induced overexpression of human (pro)renin receptor in rats resulted in the development of slowly progressive nephropathy with proteinuria. In addition, the handle-region-peptide-induced inhibition of receptor-bound prorenin significantly inhibited the development and progression of proteinuria in experimental diabetic and hypertensive animal models. Thus, the glomerular (pro)renin receptor appears to play an important role in the regulation of the glomerular filtration barrier.