GEF-H1 is activated in the glomerulus of rats with PHN. PHN was induced by a single injection of anti-Fx1A antiserum. On day 14, urine was collected, and glomeruli were isolated. A, glomerular lysates were subject to affinity precipitation with GST-RhoG17A to study the amount of active GEF-H1. Precipitates and total lysates were blotted for GEF-H1 (A) or phospho-MLC and tubulin (B). Top, representative blots; bottom, densitometric analysis. **, p < 0.01 versus control. A, n = 4 for control, n = 5 for PHN. B, n = 4 for control, n = 6 for PHN. Error bars, S.E.