Glomerular growth in the remnant kidney after a contralateral nephrectomy

A unilateral nephrectomy enhances growth or weight gain in the remaining kidney, although it is not known whether the mechanism involves the division of glomerular cells. We have isolated glomeruli from the remnant kidney at different time intervals after a nephrectomy and measured the percentage of cells in the G1, G2 + M and S phases by flow cytometry. All the steady-state glomerular cells remained in G1 phase, while a significant percentage had progressed into the S phase by 4 h after the uninephrectomy. The rise in the number of cells in the S phase gradually decreased to control values by 48 h, during which time the number of cells in both G1 and G2 + M phases increased concomitantly. Neither DNA nor RNA content per glomeruli was altered by 4 and 24 h after uninephrectomy. The data suggest an early division of the glomerular cells in the remnant kidney after a contralateral nephrectomy.