WNT 4 is a secreted glycoprotein that is critical for nephrogenesis during mesenchymal to epithelial transformation. Lately there are some experimental modles witch confirm a role of Wnt 4 during regeneration process in acute renal failure. On the other hand there are some evidence that Wnt 4 plays important role in renal fibrosis during experimental renal injury in rats that provide tubuloinerstitial fibrosis. When will Wnt 4 have a protective role or when will induce fibrosis still is not known and therefore futher studies will be necessary to gain a more precise understanding.