Puromycin aminonucleoside (NSC 3056) (30 μg/mL) markedly increases p53 protein levels in podocytes. Puromycin aminonucleoside (NSC 3056)-induced podocyte apoptosis is p53 dependent. Puromycin aminonucleoside (NSC 3056) induces podocyte apoptosis in a time-dependent manner. The IC ₅₀ values for PMAT-expressing and vector-transfected cells are 48.9 and 122.1 μM, respectively, suggesting expression of PMAT-enhanced cell sensitivity to Puromycin aminonucleoside. Puromycin aminonucleoside (NSC 3056) (250 μM) is toxic to both PMAT-expressing and vector-transfected cells. Puromycin aminonucleoside (NSC 3056) uptake in PMAT-expressing cells is fourfold higher at pH 6.6 than that at pH 7.4.

The number of podocytes per glomerulus is 95.5±17.6 in the control rats, 90.7 on Day 4 in Puromycin aminonucleoside (NSC 3056) (8 mg/100 g, i.v.)-treated nephrosis rats. The amount of nephrin per glomerulus in control rats is 1.02±0.11 fmol and those in Puromycin aminonucleoside (NSC 3056) nephrosis rats are reduced to 0.46±0.06 fmol and 0.35±0.04 fmol on Day 4 and Day 7. The nephrin amount per podocyte is significantly decreased association with the development of proteinuria in Puromycin aminonucleoside (NSC 3056) nephrosis rats. Rats given Puromycin aminonucleoside (NSC 3056) (100 mg/kg, s.c.) gain less weight and their serum creatinine levels are higher than the control rats.