Livers were obtained at sacrifice at the ages indicated and flash frozen in liquid nitrogen. RNA was extracted using TRIZOL and cDNA generated. qRT-PCR for renin, AGT, ACE and AT1R gene expression was performed using the ABI Prism system 7700 and normalized to the housekeeping gene, 18s. Expression of renin, AGT and AT1R did not differ significantly in the groups studied. However, ACE gene expression was markedly increased in PCK rat livers compared to control livers at 4 months and rose further by 6 months. (* p<0.05)