Temperature Dependence on the Passive Effects of K+ on Membrane Potential of Skeletal Muscle as an Educational Module

Abstract

The presentation reports on the implementation of a CURE (Course-based Undergraduate Research Experience) by modifying a standardized physiological laboratory protocol that measures changes in resting membrane potential concerning the concentration of extracellular potassium ions [K+]o. The CURE investigation determines how temperature influences resting membrane potential. Crayfish were used as models to empirically address the effects of temperature and [K+]o change. Experimentally, the skeletal muscle of a crayfish served as a model to obtain data due to the robust nature of the preparation for student laboratories. Graphing membrane potential in relation to both [K+]o and temperature, along with theoretical curves for the Nernst and Goldman-Hodgkin-Katz (G-H-K) equations, provided a visual representation of the significance of temperature on membrane potential and in these equations. Freely available online software was used in addressing the theoretical values one would expect for changing the variables in the G-H-K equation, which gave students a deeper understanding of its use in measuring membrane potential values. A pre- and post-survey over content comprehension and student views on the activities were also obtained.