Ca2+Release | γ | Po | KD | Examples | |
---|---|---|---|---|---|
Class I | increased or decreased3-a | decreased | increased | — | ryanodine |
Class II | increased | unchanged | increased3-b | decreased | Ca2+ caffeine, MBED, sulmazole, doxorubicin adenine nucleotides, suramin |
Class III | increased | unchanged | different from class II | halothane, heparin, bastadins | |
Class IV | decreased | unchanged | decreased3-c | increased | Mg2+, ruthenium red, aminoglycosides, FLA 365 |
Class V | decreased | unchanged | different from class IV | procaine, tetracaine phenylalkylamines dantrolene | |
Class VI | decreased | decreased | unchanged | variable | spermine, QX 314 |
Class VII | — — — — — — — delayed persistent channel inactivation3-d— — — — — — | doxorubicin, ruthenium red, neomycin |
↵3-a Ryanodine has a double effect in release experiments, as detailed in the text.
↵3-b Due to decreased lifetime of the closed channel and/or increased lifetime of the open channel.
↵3-c Due to increased lifetime of the closed channel and/or decreased lifetime of the open channel.
↵3-d This action is produced after prolonged incubation with several agents whose immediate effect belongs to a different class.
γ, channel conductance; KD , [3H]ryanodine dissociation constant.