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PubMed · 2465920

High-affinity Ca2+-binding site inhibiting Ca2+ release from sarcoplasmic reticulum.

A Argaman·V Shoshan-Barmatz
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Abstract

Ca2+ release from sarcoplasmic reticulum membranes, activated by alkaline pH occurs only when EGTA is present in the release medium. Addition of very low concentrations of Ca2+ to the medium inhibits Ca2+ release. The concentration of free Ca2+ required for 50% inhibition ranges from between 5 and 20 nM in different experiments and/or membrane preparations, irrespective of whether the free Ca2+ concentration is controlled by EGTA or CDTA. Other divalent cations such as Mn2+, Ba2+, Cu2+, Cd2+ and Mg2+ also exert an inhibitory effect on Ca2+ release, with higher or lower potency than that of Ca2+. The inactivation of Ca2+ release by Ca2+ is reversible. We suggest the involvement of high-affinity Ca2+-binding sites in the control of Ca2+ release.

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CalciumCations, DivalentEgtazic AcidHydrogen-Ion ConcentrationKineticsRuthenium RedSarcoplasmic ReticulumJournal ArticleResearch Support, Non-U.S. Gov't

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BibTeXRIS

A Argaman, V Shoshan-Barmatz. 1989-01-16. High-affinity Ca2+-binding site inhibiting Ca2+ release from sarcoplasmic reticulum.. https://doi.org/10.1016/0014-5793(89)81223-2

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