Fig. 3.

Alteration of the TGF-CTGF equilibrium. a Data suggest that if the TGF response is exaggerated, the kidney will increase sodium retention by decreasing the glomerular filtration (GFR) and activating the renin-angiotensin system. These changes would increase the blood pressure (BP) that finally will increase GFR restoring the sodium filtration but a new homeostatic BP level. At the same time, the glomerulus will be more protected to barotrauma due to the Af-Art vasoconstriction. b Contrarily, an excess of CTGF will allow the transmission of systemic BP to the glomerulus, favoring the barotrauma in the presence of systemic hypertension. At the same time, the exaggerated CTGF will induce a high GFR (hyperfiltration) that will favor sodium excretion, ameliorating the increase in BP. TGF tubule glomerular feedback, CTGF connecting tubule-glomerular feedback, Af-Art afferent arteriole