Publication Date:
1989-02-24
Description:
Gadolinium ions produce three distinct kinds of block of the stretch-activated (SA) ion channels in Xenopus oocytes: a concentration-dependent reduction in channel open time, a concentration-dependent reduction in open channel current, and a unique, steeply concentration-dependent, reversible inhibition of channel opening. This last effect reduces the probability of a channel being open from about 10(-1) at 5 microM to less than 10(-5) at 10 microM gadolinium. Calcium has effects on open time and current similar to that of gadolinium, but this channel is permeable to calcium and calcium does not completely inhibit channel activity. The availability of a blocker for SA ion channels may help to define their physiological function, and will simplify the use of oocytes as an expression system for ion channels.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Yang, X C -- Sachs, F -- DK-37792/DK/NIDDK NIH HHS/ -- New York, N.Y. -- Science. 1989 Feb 24;243(4894 Pt 1):1068-71.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉State University of New York, Buffalo 14214.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/2466333" target="_blank"〉PubMed〈/a〉
Keywords:
Animals
;
Binding, Competitive
;
Calcium/*pharmacology
;
Cations
;
Electric Conductivity
;
Female
;
Gadolinium/*pharmacology
;
Ion Channels/drug effects/*physiology
;
Kinetics
;
Oocytes/*physiology
;
Xenopus
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
,
Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics
Permalink