title: Fatty acid and sterol synthesis by hepatocytes of thermally acclimated rainbow trout (Salmo gairdneri).
abstract: Incorporation of tritium from tritiated water into lipid fractions was measured in isolated hepatocytes from rainbow trout (Salmo gairdneri) acclimated to 5 degrees C and 20 degrees C. Hepatocytes from cold-acclimated trout exhibited significantly higher rates of tritium incorporation into both fatty acid and sterol fractions at assay temperatures of 15 degrees C and 20 degrees C than did hepatocytes from warm-acclimated trout. Tritium incorporation into the fatty acid fraction was nearly temperature independent in hepatocytes from warm-acclimated trout (Q10 = 1.39) but markedly temperature dependent (Q10 = 2.63) in hepatocytes from cold-acclimated trout; in contrast, rates of sterol synthesis were more temperature dependent in warm-acclimated trout. At 5 degrees C, fatty acid lipogenesis comprised a significantly greater percentage of the total tritium incorporation in hepatocytes from warm-acclimated trout and the percentage of total lipogenesis attributable to fatty acids decreased significantly in warm-acclimated trout as the assay temperature increased; the opposite trends were observed in cold-acclimated trout.
mesh_terms: D000222:Adaptation, Physiological; D000818:Animals; D003080:Cold Temperature; D005227:Fatty Acids / Q000096:biosynthesis*; D006358:Hot Temperature; D008099:Liver / Q000378:metabolism*; D012487:Salmonidae / Q000378:metabolism*; D013261:Sterols / Q000096:biosynthesis*; D014316:Tritium; D014337:Trout / Q000378:metabolism*
chemical_list: D005227:Fatty Acids; D013261:Sterols; D014316:Tritium