Influence of pyridoxine & protein on isoenzymes of l-aspartate: 2-oxoglutarate aminotransferase in rat tissues.
Weanling male Wistar rats weighing 40 to 50 g were fed to appetite on pyridoxine-deficient diets containing vitamin-free casein 80 or 180 g/kg; pyridoxine supplement, when given, was 10 mg/kg diet. After 7 days aspartate aminotransferase activity was 50 to 60% higher in liver mitochondria of rats on high-protein diet than in those on low-protein diet; pyridoxine supplements did not affect the enzyme activity at either protein level. Liver supernatant aspartate amino-transferase was enhanced by pyridoxine supplementation at either dietary protein level, but the higher level of protein alone did not affect the supernatant enzyme activity. Aspartate aminotransferase activities of heart mitochondria and supernatant were both enhanced only by pyridoxine supplementation.