Liver, renal and subcutaneous histopathology in PEPCK-bGH transgenic pigs

Transgenic pigs were created that harboured a phospho enol pyruvate carboxykinase-bovine growth hormone construct (PEPCK-bGH). Four founder animals and two transgenic offspring from one line were evaluated between 6^1/2 and 12 months of age. There was no evidence of severe hepatic or renal lesions in these pigs, which characterised transgenic PEPCK-bGH mice previously described. While glomerular and tubular lesions in kidney sections were not identified in the transgenic pigs, mesangial cell proliferation was observed in two transgenic offspring from a single line. Additionally, glomerular size was significantly increased in four of four puberal transgenic swine when compared to age- and sex-matched controls (28.30±4.1 vs. 14.2±2.7×10⁵ μm³; representing 3 transgenic lines, p<0.05). Surprisingly, no mature adipocytes were observed in subcutaneous sections obtained in transgenic GH pigs. Histological evaluation of these transgenic pigs further illustrates the requirement for precise control of growth-related genes and their protein products.