期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1992
卷号：89
期号：21
页码：10094-10098
DOI：10.1073/pnas.89.21.10094
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Charybdotoxin (ChTX), a K+ channel blocker, depolarizes human peripheral T lymphocytes and renders them insensitive to activation by mitogen. We observed four types of K+ channels in human T cells: one voltage-activated, and three Ca(2+)-activated. To discern the mechanism by which ChTX depolarizes T cells, we examined the sensitivity of both the voltage-activated and Ca(2+)-activated K+ channels to ChTX and other peptide channel blockers. All four types were blocked by ChTX, whereas noxiustoxin and margatoxin blocked only the voltage-activated channels. All three toxins, however, produced equivalent depolarization in human T cells. We conclude that the membrane potential of resting T cells is set by voltage-activated channels and that blockade of these channels is sufficient to depolarize resting human T cells and prevent activation.
