Activation and inhibition of the calcium gate of sarcoplasmic reticulum by high-affinity ryanodine binding.
نویسندگان
چکیده
The occupancy of high-affinity ryanodine-binding sites of isolated heavy sarcoplasmic reticulum vesicles occurring in concentrated salt solutions affects ATP-dependent calcium accumulation and caffeine-induced calcium release. The initial suppression of calcium uptake is followed by a marked uptake activation resulting in a reduction of the final calcium level in the medium. Simultaneously, caffeine-induced calcium release is blocked. The dependence of inhibition of calcium uptake and caffeine-induced calcium release observed in assay media containing physiological concentrations of magnesium and ATP on the concentration of ryanodine corresponds to the drug's effectiveness in living muscles.
منابع مشابه
Dantrolene Inhibition of Sarcoplasmic Reticulum Ca Release by Direct and Specific Action at Skeletal Muscle Ryanodine Receptors*
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The skeletal muscle relaxant dantrolene inhibits the release of Ca2+ from the sarcoplasmic reticulum during excitation-contraction coupling and suppresses the uncontrolled Ca2+ release that underlies the skeletal muscle pharmacogenetic disorder malignant hyperthermia; however, the molecular mechanism by which dantrolene selectively affects skeletal muscle Ca2+ regulation remains to be defined. ...
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عنوان ژورنال:
- FEBS letters
دوره 221 1 شماره
صفحات -
تاریخ انتشار 1987