We found a match
Your institution may have access to this item. Find your institution then sign in to continue.
- Title
All-or-none response of the Ca<sup>2+</sup>-dependent K<sup>+</sup> channel in inside-out vesicles.
- Authors
García-Sancho, Javier; Sanchez, Ana; Herreros, Benito
- Abstract
In several cell lines, an increase in the intracellular Ca2+ concentration elicits an increase in the membrane permeability to K+(Rb+) by activation of the so-called Ca2+-dependent K+ channel1. The human red cell has been widely used to study this transport system2. As Ca2+ (refs 3,4) and other possible modulators5,6 act on the intracellular side of the membrane, a preparation of everted vesicles would be most useful for investigating such actions. Although several previous studies in inside-out vesicles7 have been unsatisfactory8-10, a new vesiculation procedure that preserves Ca2+-dependent K+ transport has recently been reported11,12. Using this preparation we now find that each vesicle responds to Ca2+ in an all-or-none fashion, the number of activated (permeable to 86Rb) vesicles increasing with Ca2+ concentration between 10−8 and 10−6M. This behaviour probably reflects the all-or-none response of individual K+ channel units. The sensitivity to Ca2+ is decreased by Mg2+.
- Publication
Nature, 1982, Vol 296, Issue 5859, p744
- ISSN
0028-0836
- Publication type
Article
- DOI
10.1038/296744a0