LIPOGENIC ENZYME-ACTIVITIES IN LIVER OF ATLANTIC SALMON (SALMO-SALAR, L)

1. Activities of four hepatic lipogenic enzymes were studied: NADP-isocitrate dehydrogenase (ICDH), malic enzyme (ME), glucose-6-phosphate dehydrogenase (G6PDH) and 6-phosphogluconate dehydrogenase (6PGDH). 2. Dietary effects on plasma levels of triacylglycerol (TAG) and non-esterified fatty acids (NEFA), were also examined. 3. The study was based on the same fish and diets as in a previous study (Arnesen et al., submitted). 4. The fact that we were able to measure activities of lipogenic enzymes, demonstrates that Atlantic salmon are capable of producing reducing equivalents essential for fatty acid synthesis through the same pathways as found in other species. 5. Absorbed fat (calculated value) was found to be negatively correlated to lipogenic enzyme activities (G6PDH in the oat diet series and 6PGDH, ICDH and ME in the Maize/Oat diet series). 6. No significant correlation was found between lipogenic enzyme activities and absorbed starch (calculated value). 7. Neither the amount of absorbed starch nor the amount of absorbed fat was found to have any effect on plasma levels of TAG or NEFA.