Figure. 1.

Structure of the glomerular filtration barrier. (A) Electron micrograph of a normal rat glomerulus showing the basic structures of the filtration barrier. (B) A rat glomerulus 7 days after exposure in vivo to an adenovirus expressing active transforming growth factor-beta (TGF-β) demonstrates podocyte de-differentiation and foot process effacement which results in proteinuria. An adenovirus expressing active TGF-β was infused via the left renal artery in Sprague Dawley rats. Gene expression was confirmed by measuring urinary TGF-β protein. Foot process effacement was quantified, as was expression of nephrin and synaptopodin. These features suggested podocyte dedifferentiation [37].