Studying the mechanosensitivity of voltage-gated channels using oocyte patches.
The mechanosensitivity of voltage-gated (VG) channels is of biophysical, physiological. and pathophysiological interest. Xenopus oocytes offer a critical advantage for investigating the electrophysiology of recombinant VG channels subjected to membrane stretch, namely, the ability to monitor macroscopic current from membrane patches. High-density channel expression in oocytes makes for macroscopic current in conventional-size, mechanically sturdy patches. With the patch configuration, precisely the same membrane that is voltage-clamped is the membrane subjected to on-off stretch stimuli. With patches, meaningful stretch dose responses are possible. Experimental design should facilitate within-patch comparisons wherever possible. The mechanoresponses of some VG channels depend critically on patch history. Methods for minimizing and coping with interference from endogenous voltage-dependent and stretch-activated endogenous channels are described.
Morris
Catherine E
CE
Department of Medicine, University of Ottawa, Ontario, Canada.
Juranka
Peter F
PF
Lin
Wei
W
Morris
Terence J
TJ
Laitko
Ulrike
U
D000818:Animals; D005260:Female; D015640:Ion Channel Gating / Q000502:physiology*; D008465:Mechanoreceptors / Q000502:physiology*; D040542:Mechanotransduction, Cellular / Q000502:physiology; D009865:Oocytes / Q000502:physiology*; D018408:Patch-Clamp Techniques / Q000379:methods*; D014981:Xenopus