Description: IC50 Value: N/A Puromycin Aminonucleoside (3'-Amino-3'-deoxy-N6,N6-dimethyladenosine) is the aminonucleoside portion of the antibiotic puromycin. It is a puromycin analog which does not inhibit protein synthesis or induce apoptosis. Used in the study of focal and segmental glomerulosclerosis and in the induction of nephrosis in rats. in vitro: PA-induced apoptosis was associated with increased p53 expression, which was completely blocked by dexamethasone. Furthermore, the inhibition of p53 by the p53 inhibitor pifithrin-alpha protected against PA-induced apoptosis. Dexamethasone also lowered the increase in the proapoptotic Bax, which was increased by PA, and increased expression of the antiapoptotic Bcl-xL protein [1]. Expression of PMAT in Madin-Darby canine kidney cells significantly increased cell sensitivity to PAN [2]. in vivo: The number of podocytes per glomerulus was 95.5±17.6 in the control rats, 90.7±19.2 on Day 4 and 90.7±26.2 on Day 7 in PAN nephrosis rats. The amount of nephrin per glomerulus in control rats was 1.02±0.11 fmol and those in PAN nephrosis rats were reduced to 0.46±0.06 fmol and 0.35±0.04 fmol on Day 4 and Day 7 [3]. Toxicity: The 24-h urinary protein excretion of treated rats compared with controls (PAN rats) 9 days after PAN injection was 16 +/- 2 mg and 524 +/- 55 mg, respectively (p < .01). Morphological examination also demonstrated that the glomerular epithelial cells were protected against PAN-induced damage [4]. Clinical trial: N/A