Meeting Abstract

P2.91  Thursday, Jan. 5  Thermal acclimation of locomotor performance in the Eastern Newt (Notophthalmus viridescens). MINEO, P.M.*; SCHAEFFER, P.J.; Miami University; Miami University mineopm@muohio.edu

Biochemical acclimation to temperature is evident in some amphibians, but the degree to which this response is associated with locomotor performance is uncertain. Previous studies demonstrate biochemical acclimation of oxidative enzymes in muscle of the Eastern Newt (Notophthalmus viridescens). Our goal is to determine how the acclimation of these metabolic enzymes is correlated with the thermal sensitivity of locomotor performance in these animals. We acclimated N. viridecens to 25°C, 15°C, and 5°C for 12 weeks. Next, we measured burst-swimming speed and swam newts to exhaustion at 5°C, 10°C, 15°C, 20°C, 25°C and 30°C in a temperature-controlled track. The activities of lactate dehydrogenase, citrate synthase, and cytochrome c oxidase in muscle extracted from these animals was measured across the same temperature range as the locomotor tests to determine if thermal sensitivity of enzyme function is matched with the thermal sensitivity of burst and endurance locomotion, as well as whether phenotypic flexibility of enzyme function is associated with phenotypic flexibility of locomotor performance.