Because NE is considered the prime target for AAT mediated protease inhibition [13]–[18], we assessed whether: 1) AKI up-regulates renal cortical NE gene expression (assessed by NE mRNA levels); 2) whether NE is cytotoxic to proximal tubule cells; and 3) whether AAT might exert cytoprotection via its NE inhibitory effect. The gene discussed is SERPINA1; the disease is acute kidney injury.