Metabolic lipid regulation during developmental stress : fatty acid dynamics in fasting northern elephant seals.

Long chain fatty acids (LCFA) are important as fuel during exercise in humans, yet have pathological consequences during LCFA overabundance. The northern elephant seal (NES) (Mirounga angustirostris) is a temporally insulin resistant, deep-diving marine mammal reliant on fatty acid oxidation during seasonal fasting. Over the fast, NES females and weaned pups were found to oppositely utilize monounsaturated and saturated fatty acids, while polyunsaturated fatty acids generally increased in both age groups. Fatty acid transporter proteins (FATP) CD36, FATP1, FATP4 and binding protein 3 (FABP3) were detected in adult males, adult females, and pups. This thesis is the first documentation of these FATPs and FABPs in all NES age classes and expands current knowledge of lipid utilization in a mammal accustomed to a LCFA-rich diet.