Selective activation of Ca2+-activated K+ channels by co-localized Ca2+ channels in hippocampal neurons

Neil V. Marrion () and Steven J. Tavalin
Additional contact information
Neil V. Marrion: Vollum Institute, Oregon Health Sciences University Portland
Steven J. Tavalin: Vollum Institute, Oregon Health Sciences University Portland

Nature, 1998, vol. 395, issue 6705, 900-905

Abstract: Abstract Calcium entry through voltage-gated calcium channels can activate either large- (BK) or small- (SK) conductance calcium-activated potassium channels. In hippocampal neurons, activation of BK channels underlies the falling phase of an action potential and generation of the fast afterhyperpolarization (AHP)1,2. In contrast, SK channel activation underlies generation of the slow AHP after a burst of action potentials3. The source of calcium for BK channel activation is unknown, but the slow AHP is blocked by dihydropyridine antagonists4,5, indicating that L-type calcium channels provide the calcium for activation of SK channels. It is not understood how this specialized coupling between calcium and potassium channels is achieved. Here we study channel activity in cell-attached patches from hippocampal neurons and report a unique specificity of coupling. L-type channels activate SK channels only, without activating BK channels present in the same patch. The delay between the opening of L-type channels and SK channels indicates that these channels are 50–150 nm apart. In contrast, N-type calcium channels activate BK channels only, with opening of the two channel types being nearlycoincident. This temporal association indicates that N and BK channels are very close. Finally, P/Q-type calcium channels do not couple to either SK or BK channels. These data indicate an absolute segregation of coupling between channels, and illustrate the functional importance of submembrane calcium microdomains.

Date: 1998
References: Add references at CitEc
Citations:

Downloads: (external link)
https://www.nature.com/articles/27674 Abstract (text/html)
Access to the full text of the articles in this series is restricted.

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:nat:nature:v:395:y:1998:i:6705:d:10.1038_27674

Ordering information: This journal article can be ordered from
https://www.nature.com/

DOI: 10.1038/27674

Access Statistics for this article

Nature is currently edited by Magdalena Skipper

More articles in Nature from Nature
Bibliographic data for series maintained by Sonal Shukla () and Springer Nature Abstracting and Indexing ().