An optical lever was designed for studying physical displacements associated with electrophysiological activation of lobster nerve bundles. Stimulation current pulses generated a compound action potential volley, and upward physical displacements of <1 nm were recorded. The swelling displacement propagated in the same direction as the action potential volley, occurred simultaneously with the action potentials, and required 10 ms to relax after the electrical potential was restored. For comparison with previous reports, we also recorded the displacement of Nitella internodes associated with electrical stimulation. We found that a rapid swelling displacement (∼10 nm) was followed by a larger, slow-shrinking displacement (∼100 nm).
© 2003 Optical Society of America
Original Manuscript: September 26, 2002
Revised Manuscript: January 7, 2003
Published: June 1, 2003
Xin-Cheng Yao, David M Rector, and John S. George, "Optical lever recording of displacements from activated lobster nerve bundles and Nitella internodes," Appl. Opt. 42, 2972-2978 (2003)