Rapid temperature jump by infrared diode laser irradiation for patch-clamp studies.
Several thermal TRP ion channels have recently been identified. These channels are directly gated by temperature, but the mechanisms have remained elusive. Studies of their temperature gating have been impeded by lack of methods for rapid alteration of temperature in live cells. As a result, only measurements of steady-state properties have been possible. To solve the problem, we have developed an optical approach that uses recently available infrared diode lasers as heat sources. By restricting laser irradiation around a single cell, our approach can produce constant temperature jumps over 50 degrees C in submilliseconds. Experiments with several heat-gated ion channels (TRPV1-3) show its applicability for rapid temperature perturbation in both single cells and membrane patches. Compared with other laser heating approaches such as those by Raman-shifting of the Nd:YAG fundamentals, our approach has the advantage of being cost effective and applicable to live cells while providing an adequate resolution for time-resolved detection of channel activation.
Yao
Jing
J
Department of Physiology and Biophysical Sciences, State University of New York at Buffalo, Buffalo, New York 14214, USA.
Liu
Beiying
B
Qin
Feng
F
D000465:Algorithms; D000818:Animals; D002460:Cell Line; D003198:Computer Simulation; D004553:Electric Conductivity; D006801:Humans; D007259:Infrared Rays; D054023:Lasers, Semiconductor; D008564:Membrane Potentials / Q000502:physiology; D051379:Mice; D008954:Models, Biological; D018408:Patch-Clamp Techniques / Q000379:methods*; D051381:Rats; D050916:TRPV Cation Channels / Q000378:metabolism; D013696:Temperature; D014982:Xenopus laevis
D050916:TRPV Cation Channels; C493922:Trpv1 protein, rat; C476722:Trpv2 protein, rat; C486760:Trpv3 protein, mouse