Action Potentials and Electrical Excitability

This lecture covers the fundamentals of action potentials and electrical excitability, focusing on the mechanisms behind the generation and propagation of action potentials in neurons. Starting with the basics of membrane potential responses and the role of microelectrodes, it delves into the insights drawn from the 'giant axon' of a squid. The lecture explains the voltage clamp technique for studying membrane currents and the conductances of Na+ and K+ ions. It also discusses the concepts of activation, inactivation, and deactivation of ion channels, as well as the historical significance of Hodgkin & Huxley's work. Furthermore, it explores the saltatory conduction in myelinated axons and the properties of voltage-gated Na+ and K+ channels.