Meeting Abstract

P2.132  Monday, Jan. 5  Are Skeletal Muscle Adaptations to Diving in Weddell Seals (Leptonychotes weddelli) a Response to Environmental Stimuli? DE MIRANDA JR., M.A.*; MAYBERRY, J.K.; PEARSON, L.E.; KANATOUS, S.B.; Colorado State University; Colorado State University; University of Alaska Anchorage; Colorado State University Jaime.Mayberry@colostate.edu

The purpose of this study was to determine whether the elevated aerobic capacities in the skeletal muscle of Weddell seals (Leptonychotes weddelli) is due to a genetic predisposition or a response to environmental conditions. Cells were harvested from adult Weddell seal longissimus dorsi, the primary swimming muscle. The primary cells were compared to a C₂C₁₂ cell line under normoxic (21% O₂) and hypoxic (1% O₂) conditions for six days, as the myoblasts differentiated into mature myotubes. Myoglobin concentrations and aerobic enzyme assays were used to measure skeletal muscle aerobic capacity. We hypothesized that there would be a significant difference between seal and mouse cells under hypoxic conditions. However, we found no significant difference in citrate synthase activity or myoglobin concentrations between the seal and mouse cells under normoxic or hypoxic conditions. This indicates that the adaptations to diving in Weddell seal skeletal muscle are not determined by a genetic predisposition, but are a response to environmental stimuli.