Harold Lecar

Professor (Molecular & Cell Biology)

Email: hlecar@berkeley.edu

Research areas: Cellular and Molecular Neuroscience, Cellular and Molecular Neuroscience

We study the membrane processes underlying excitation in the nervous system, particularly the gated ionic channels involved in electrical and chemical excitation. During the gating process, ionic channel proteins switch back and forth between ion-conducting and nonconducting configurations. These transitions can be observed in individual channels using the patch-electrode technique. Gated channels are involved in a great variety of membrane transduction processes including nerve impulse conduction, synaptic transmission, secretion, immune responses and sensory reception.

If we understand the gating properties of ion channels, we can construct mathematical models of the behavior of excitable cells. Stochastic excitation phenomena such as fluctuations in firing thresholds, firing frequencies, and the summation of random postsynaptic responses constitute the natural noise of the nervous system. The design of excitable cells�whether they function as oscillators, or encoders of sensory information, or controllers of secretion�is determined by the types and densities of the channel proteins in the cell membrane.

Selected Publications

Lecar, H., & Morris, C. E. 1993. Biophysics of mechanotransduction Mechanoreception by the Vascular Wall, G. M. Rubanyi, ed., Futura Publishing Co: 1-11.

Sachs, F. & Lecar, H. 1991. Stochastic models for mechanical transduction Biophys. J. 59: 1143–1145.