Properties of immunoaffinity purified 106-kDa Ca2+ release channels from the skeletal sarcoplasmic reticulum

Hilkert, R. J.; Zaidi, Nikhat F.; Shome, Kuntala; Nigam, Meenakshi; Lagenaur, Carl F.; Salama, Guy

doi:10.1016/0003-9861(92)90043-v

Cited by 18 publications

(6 citation statements)

References 32 publications

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“…Immunological analysis using polyclonal and monoclonal antibodies indicated that SH-GA TED SR Ca2+ RELEASE IN SKINNED FIBRES the 106 kDa protein was distinct from Ca2+, Mg2+-ATPase and 565 kDa junctional feet protein (Zaidi et al 1989a). Incorporation of 106 kDa proteins in planar bilayers revealed the presence of SR Ca2+-release channels with characteristics similar to those described for junctional feet proteins (Zaidi et al 1989b;Hilkert, Zaidi, Nigam, Shome, Lagenaur & Salama, 1992). Moreover, sulphydryl oxidizing (i.e.…”

Section: Mechanism and Site Of Action Of Sulphydryl Reagentssupporting

confidence: 61%

Sulphydryl reagents trigger Ca2+ release from the sarcoplasmic reticulum of skinned rabbit psoas fibres.

Salama

Abramson

Pike

1992

The Journal of Physiology

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SUMMARY1. By analogy with studies on sarcoplasmic reticulum (SR) vesicles, Ca2+ release induced by heavy metals and mercaptans (e.g. cysteine) was investigated in rabbit skinned psoas fibres through measurements of isometric tension.2. Heavy metals (at 2-5 /tM) elicited phasic contractions by triggering Ca2+ release from the SR and had the following order of potency: Hg2+ > Cu2+ > Cd2+ > Ag+ > Ni2+. Higher concentrations produced tonic contractions due to maintained high Ca2+ permeability of SR membranes.3. Contractions induced by heavy metals required a functional and Ca2+-loaded SR, were dependent on [Ca2+]free, blocked by Ruthenium Red (RR), inhibited by free Mg2+ and reduced glutathione (GSH) but not by oxidized glutathione (GSSG). Such contractions were not elicited through direct interactions) of heavy metals with the myofilaments.4. In the presence of catalytic concentrations of Hg2+ or Cu2+ (2-5 /UM), additions of cysteine (25-100 /LM) elicited rapid twitches, producing 70 % of maximal force with a time to half-peak of 2 s. Contractions induced by cysteine plus a catalyst required a functional SR network, were dependent on free [Mg2+] and were blocked by RR or GSH but not by GSSG.5. In the presence of Hg2+ (2-5 ,uM), low concentrations of cysteine (10 /uM) elicited tonic contractures, but subsequent or higher additions of cysteine (50-100 uM) caused further SR Ca2+ release and tension, followed by rapid and full relaxation.6. High cysteine (200-250 /tM, without Cu2+ or Hg2+) blocked contractions elicited by Cl-induced depolarization of sealed T-tubules. High cysteine probably acted as a sulphydryl reducing agent which promoted rapid relaxation of the fibres through the closure of Ca2+-release channels and ATP-dependent re-uptake of Ca2+ by the SR. 7. In some batches of skinned fibres (-10%), cysteine (5-50 /tM) alone (without Hg2+ or Cu2+ catalyst) produced rapid twitches. This implied that the catalysts) necessary to promote the sulphydryl oxidation reaction with exogenously added cysteine may be present in intact fibres but is usually lost by the skinning procedure.

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Section: Mechanism and Site Of Action Of Sulphydryl Reagentssupporting

confidence: 61%

Sulphydryl reagents trigger Ca2+ release from the sarcoplasmic reticulum of skinned rabbit psoas fibres.

Salama

Abramson

Pike

1992

The Journal of Physiology

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“…The SH-oxidizing reagents that have been tested compete with ryanodine binding to SR vesicles, which indicates these agents act at or near the ryanodine binding site (Zaidi et al, 1989). The activation or opening of Ca 2ϩ -release channels by SH-oxidizing reagents could be reversed by SH-reducing agents (e.g., cysteine, dithiothreitol) (Hilkert et al, 1992). However, cysteine and dithiothreitol had no effect on the observed effects elicited by hypoxanthine-xanthine oxidase reaction on 45 Ca 2ϩ efflux and single-channel gating behavior (data not shown).…”

Section: Experimental Additionmentioning

confidence: 91%

Superoxide Anion Radical-Triggered Ca²⁺Release from Cardiac Sarcoplasmic Reticulum through Ryanodine Receptor Ca²⁺Channel

1998

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The ryanodine receptor Ca2+ channel (RyRC) constitutes the Ca2+-release pathway in sarcoplasmic reticulum (SR) of cardiac muscle. A direct mechanical and a Ca2+-triggered mechanism (Ca2+-induced Ca2+ release) have been proposed to explain the in situ activation of Ca2+ release in cardiac muscle. A variety of chemical oxidants have been shown to activate RyRC; however, the role of modification induced by oxygen-derived free radicals in pathological states of the muscle remains to be elucidated. It has been hypothesized that oxygen-derived free radicals initiate Ca2+-mediated functional changes in or damage to cardiac muscle by acting on the SR and promoting an increase in Ca2+ release. We confirmed that superoxide anion radical (O2-) generated from hypoxanthine-xanthine oxidase reaction decreases calmodulin content and increases 45Ca2+ efflux from the heavy fraction of canine cardiac SR vesicles; hypoxanthine-xanthine oxidase also decreases Ca2+ free within the intravesicular space of the SR with no effect on Ca2+-ATPase activity. Current fluctuations through single Ca2+-release channels have been monitored after incorporation into planar phospholipid bilayers. We demonstrate that activation of the channel by O2- is dependent of the presence of calmodulin and identified calmodulin as a functional mediator of O2--triggered Ca2+ release through the RyRC. For the first time, we show that O2- stimulates Ca2+ release from heavy SR vesicles and suggest the importance of accessory proteins such as calmodulin in modulating the effect of O2-. The decreased calmodulin content induced by oxygen-derived free radicals, especially O2-, is a likely mechanism of accumulation of cytosolic Ca2+ (due to increased Ca2+ release from SR) after reperfusion of the ischemic heart.

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“…Ag ϩ induces Ca 2ϩ release via oxidizing SH groups on the physiological release channel, the RyR, and this can be inhibited by SH reducing agents such as dithiothreitol (26,45,46,53,56). Although Ag ϩ -induced Ca 2ϩ release is specific for Ca 2ϩ release from the RyR (14), several limitations exist in our methodology.…”

Section: Fatigue Depresses Ag ϩ -Induced Sr Ca 2ϩ Release and Sr Ca 2mentioning

confidence: 99%

Effects of fatigue and training on sarcoplasmic reticulum Ca²⁺regulation in human skeletal muscle

Li¹,

Wang

Fraser³

et al. 2002

Journal of Applied Physiology

112

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Little is known about fatigue and training effects on sarcoplasmic reticulum (SR) function in human muscle, and we therefore investigated this in eight untrained controls (UT), eight endurance-trained (ET), and eight resistance-trained athletes (RT). Muscle biopsies (vastus lateralis) taken at rest and after 50 maximal quadriceps contractions (180 degrees/s, 0.5 Hz) were analyzed for fiber composition, metabolites and maximal SR Ca(2+) release, Ca(2+) uptake, and Ca(2+)-ATPase activity. Fatigue reduced (P < 0.05) Ca(2+) release (42.1 +/- 3.8%, 43.4 +/- 3.9%, 31.3 +/- 6.1%), Ca(2+) uptake (43.0 +/- 5.2%, 34.1 +/- 4.6%, 28.4 +/- 2.8%), and Ca(2+)-ATPase activity (38.6 +/- 4.2%, 48.5 +/- 5.7%, 29.6 +/- 5.0%), in UT, RT, and ET, respectively. These decreases were correlated with fatigability and with type II fiber proportion (P < 0.05). Resting SR measures were correlated with type II proportion (r > or = 0.51, P < 0.05). ET had lower resting Ca(2+) release, Ca(2+) uptake, and Ca(2+)-ATPase (P < 0.05) than UT and RT (P < 0.05), probably because of their lower type II proportion; only minor effects were found in RT. Thus SR function is markedly depressed with fatigue in controls and in athletes, is dependent on fiber type, and appears to be minimally affected by chronic training status.

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Properties of immunoaffinity purified 106-kDa Ca2+ release channels from the skeletal sarcoplasmic reticulum

Cited by 18 publications

References 32 publications

Sulphydryl reagents trigger Ca2+ release from the sarcoplasmic reticulum of skinned rabbit psoas fibres.

Sulphydryl reagents trigger Ca2+ release from the sarcoplasmic reticulum of skinned rabbit psoas fibres.

Superoxide Anion Radical-Triggered Ca²⁺Release from Cardiac Sarcoplasmic Reticulum through Ryanodine Receptor Ca²⁺Channel

Effects of fatigue and training on sarcoplasmic reticulum Ca²⁺regulation in human skeletal muscle

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Properties of immunoaffinity purified 106-kDa Ca2+ release channels from the skeletal sarcoplasmic reticulum

Cited by 18 publications

References 32 publications

Sulphydryl reagents trigger Ca2+ release from the sarcoplasmic reticulum of skinned rabbit psoas fibres.

Sulphydryl reagents trigger Ca2+ release from the sarcoplasmic reticulum of skinned rabbit psoas fibres.

Superoxide Anion Radical-Triggered Ca2+Release from Cardiac Sarcoplasmic Reticulum through Ryanodine Receptor Ca2+Channel

Effects of fatigue and training on sarcoplasmic reticulum Ca2+regulation in human skeletal muscle

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Product

Resources

About

Superoxide Anion Radical-Triggered Ca²⁺Release from Cardiac Sarcoplasmic Reticulum through Ryanodine Receptor Ca²⁺Channel

Effects of fatigue and training on sarcoplasmic reticulum Ca²⁺regulation in human skeletal muscle