Figure 8: Effect of steroid hormones on renal stem/progenitor cells could be divided into four categories: (a) Lack of SBA-label, (b) Formation of cell islets, (c-e) extensive cell clusters and (f) tubule development with intensive SBAlabel. (a) 17-a-hydroxyprogesterone did not reveal a positive effect on renal stem/progenitor cell development. (b) Formation of SBA-labeled cell islets was found after treatment with dihydrotestosterone. Extensive formation of SBAlabeled cell clusters was detected after application of (c) testosterone, (d) 17-ß-estradiol and (e) dexamethasone. (f) SBA-labeled tubule formation was observed after aldosterone application.