쥐 hepatocytes에서 lipogenic enzyme인 glucose-6-phosphate dehydrogenase(G6PD)와 apolipoprotein E(apoE) 합성의 조절을 조사하였다. G6PD와 apoE의 합성속도는 제한된 영양 상태에 있는 쥐 hepatocytes로부터 immunoprecipitation과 SDS polyacrylamide gel electrophoresis로 측정하였다. 2일간 절식 후 3일간 고탄수화물을 섭취한 경우, G6PD 합성은 증가하였으나 apoE 합성은 변화되지 않았다. 한편 절식한 쥐에서는 G6PD 합성은 감소된 반면 apoE 합성은 증가되었다. 2일간 절식 후 3일간 고탄수화물을 섭취시키고 dibutyryl cAMP로 처리한 경우, apoE 합성은 영향을 받지 않았으나, G6PD는 그 합성이 감소되었다. 이 결과는 lipogenic enzyme인 G6PD와 apoE의 합성은 일률적으로 조절되지 않음을 시사해준다.
Rat hepatocytes were used to examine whether there is a coordinate regulation of lipogenic enzyme, glucose-6-phosphate dehydrogenase (G6PD) and apolipoprotein E(apoE) synthesis by assessing rates of synthesis of both G6PD and apoE in each animal. The rates of synthesis of G6PD and apoE were determined by immunoprecipitation and SDS polyacrylamide gel electrophoresis (PAGE) of hepatocytes prepared from rats in a defined nutritional state. The large increase in G6PD synthesis was observed in rats fasted for 2 days (d) and refed a high carbohydrate diet for 3d while apoE synthesis was not affected. Fasting along caused a decrease in G6PD synthesis but an increase in apoE synthesis. When rats were fasted for 2d, refed a high carbohydrate diet for 3d, and then injected with dibutyryl cAMP, apoE synthesis was unaffected but G6PD synthesis was decreased. The combined data indicate that apoE synthesis is not coordinately regulated with lipogenic enzyme, G6PD synthesis or lipogenesis.
