Renal fibrosis and the renin-angiotensin system.

These data demonstrate that regression of biopsy-proven glomerulosclerosis can be achieved in various experimental settings. The potential importance of the RAS in renal fibrosis is underscored by the effectiveness of therapies that aim to inhibit its manifold actions, including induction of PAI-1. An understanding of the interactions of the RAS with the immune response, aldosterone, and PAI-1, as well as the dynamic control of cell proliferation, apoptosis, and regeneration, is now evolving. Ongoing studies will establish which of these recent provocative findings from animal models are relevant to human diseases, and may lead to optimal therapies to fore-stall progression and perhaps even induce regression of sclerosis.