Fig. 1.

Schematic illustration of the antidiuretic action of soluble (pro)renin receptor (sPRR). Experimental evidence is available to demonstrate that sPRR stimulates renal aquaporin-2 expression and promotes urine concentrating capability by mediating the antidiuretic action of vasopressin (VP). Since sPRR acts downstream of VP type 2 receptor (V2R) in the kidney, it is effective in management of nephrogenic diabetes insipidus (NDI) induced by V2R antagonism. On the other hand, PRR is shown to regulate VP release from the central nervous system and such action is speculated to be mediated by sPRR. Solid line, experimentally confirmed; dashed line, not confirmed. CDI, central diabetes insipidus.