Expression of sarcoplasmic reticulum Ca2+ transport proteins in cold-acclimating ducklings

The relationship between the cold-induced increase in sarcoplasmic reticulum (SR) Ca2+ transport proteins and the development of muscular nonshivering theermogenesis (NST) was investigated by determining the time course of expression of the sarcoplasmic or endoplasmic reticulum Ca(2+)-ATPase (SERCA), Ca2+ release channel, and calsequestrin in control and cold-acclimating ducklings. 45Ca2+ uptake and [3H]ryanodine binding measurements with skeletal muscle homogenates showed that a cold acclimation period of approximately 4 wk was required to observe a substantial increase in Ca(2+)-ATPase activity and Ca2+ release channel content, which correlates well with NST development Immunoblot analysis of muscle homogenates showed no differences in calsequestrin levels but revealed that the decrease in SERCA2a content was delayed in cold-acclimating birds and that the SERCA1 level was increased after 4 wk of cold acclimation. The persistence of SERCA2a may be related to shivering thermogenesis occurring preferentially in slow-twitch fibers. SERCA1 may account for most of the cold-induced increase in 45Ca2+ uptake activity, suggesting the preferential occurrence of a Ca(2+)-dependent NST in fast-twitch fibers.

Download Full-text

Calcium accumulation by the sarcoplasmic reticulum in two populations of chemically skinned human muscle fibers. Effects of calcium and cyclic AMP.

The Journal of General Physiology ◽

10.1085/jgp.79.4.603 ◽

1982 ◽

Vol 79 (4) ◽

pp. 603-632 ◽

Cited By ~ 51

Author(s):

G Salviati ◽

M M Sorenson ◽

A B Eastwood

Keyword(s):

Sarcoplasmic Reticulum ◽

Cyclic Amp ◽

Muscle Fibers ◽

Human Muscle ◽

Wide Range ◽

Ca Uptake ◽

Human Muscles ◽

Slow Twitch ◽

Slow Twitch Fibers ◽

Fast Twitch

In previous efforts to characterize sarcoplasmic reticulum function in human muscles, it has not been possible to distinguish the relative contributions of fast-twitch and slow-twitch fibers. In this study, we have used light scattering and 45Ca to monitor Ca accumulation by the sarcoplasmic reticulum of isolated, chemically skinned human muscle fibers in the presence and absence of oxalate. Oxalate (5 mM) increased the capacity for Ca accumulation by a factor of 35 and made it possible to assess both rate of Ca uptake and relative sarcoplasmic reticulum volume in individual fibers. At a fixed ionized Ca concentration, the rate and maximal capacity (an index of sarcoplasmic reticulum volume) both varied over a wide range, but fibers fell into two distinct groups (fast and slow). Between the two groups, there was a 2- to 2.5-fold difference in oxalate-supported Ca uptake rates, but no difference in average sarcoplasmic reticulum volumes. Intrinsic differences in sarcoplasmic reticulum function (Vmax, K0.5, and n) were sought to account for the distinction between fast and slow groups. In both groups, rate of Ca accumulation increased sigmoidally as [Ca++] was increased from 0.1 to 1 microM. Apparent affinities for Ca++ (K0.5) were similar in the two groups, but slow fibers had a lower Vmax and larger n values. Slow fibers also differed from fast fibers in responding with enhanced Ca uptake upon addition of cyclic AMP (10(-6) M, alone or with protein kinase). Acceleration by cyclic AMP was adequate to account for adrenaline-induced increases in relaxation rates previously observed in human muscles containing mixtures in fast-twitch and slow-twitch fibers.

Download Full-text

Sarcoplasmic reticulum Ca(2+)-ATPase and ryanodine receptor in cold-acclimated ducklings and thermogenesis

AJP Cell Physiology ◽

10.1152/ajpcell.1993.265.2.c507 ◽

1993 ◽

Vol 265 (2) ◽

pp. C507-C513 ◽

Cited By ~ 59

Author(s):

E. Dumonteil ◽

H. Barre ◽

G. Meissner

Keyword(s):

Sarcoplasmic Reticulum ◽

Atpase Activity ◽

Ryanodine Receptor ◽

Cold Exposure ◽

Gastrocnemius Muscle ◽

Sodium Dodecyl ◽

Immunoblot Analysis ◽

Release Channel ◽

Cairina Moschata ◽

Whole Muscle

In birds, prolonged cold exposure induces the development of a nonshivering thermogenesis (NST) of muscular origin. NST is characterized by an increased heat production, which may be achieved by an increased ATP-dependent cycling of Ca2+ between the sarcoplasmic reticulum (SR) and cytosolic compartments in muscle. In this study, the effects of prolonged cold exposure on SR function were assessed by determining the contents of the SR Ca(2+)-ATPase and Ca2+ release channel (ryanodine receptor) in the gastrocnemius muscle of ducklings (Cairina moschata) kept at thermoneutrality (25 degrees C) or cold acclimated (4 degrees C, 5 wk). Measurement of oxalate-supported 45Ca2+ uptake by whole muscle homogenates revealed that the SR Ca(2+)-ATPase activity, and fraction of vesicles containing a ryanodine-sensitive Ca2+ release channel were increased by 30-50% in response to prolonged cold exposure. Sodium dodecyl sulfate-polyacrylamide gel and immunoblot analysis, 45Ca2+ uptake, Ca(2+)-ATPase activity and [3H]ryanodine binding measurements with unfractionated and "heavy" SR membrane fractions also indicated an elevated Ca(2+)-ATPase and Ca2+ release channel content in cold-acclimated ducklings. These results showed that the contents of two components directly involved in Ca2+ cycling by the SR are increased by cold acclimation, and we suggest that this is related to NST.

Download Full-text

Different induction of biogenic amine accumulation during cold acclimation in Triticeae genotypes with varying freezing tolerance

Revista Brasileira de Botânica ◽

10.1007/s40415-020-00690-9 ◽

2021 ◽

Vol 44 (1) ◽

pp. 11-15

Author(s):

Muhammad Ahsan Asghar ◽

Zsuzsa Mednyánszky ◽

Livia Simon-Sarkadi ◽

Gábor Kocsy

Keyword(s):

Biogenic Amines ◽

Cold Acclimation ◽

Freezing Tolerance ◽

Biogenic Amine ◽

Time Course ◽

Protective Role ◽

Wheat Genotype ◽

Continuous Increase ◽

Acclimation Period ◽

Amine Content

AbstractThe appropriate timing of the accumulation of biogenic amines is very important during cold acclimation due to their direct protective role and their involvement in the signaling processes. The time course of changes in the amount of six of them was compared during a 3-week acclimation period in a freezing tolerant and a sensitive genotype of rye, barley and wheat. In general, a greater and faster cold-induced increase in biogenic amine content was observed in the tolerant genotypes of the three species compared to the sensitive ones. This change was very quick in the case of putrescine, spermidine and cadaverine reaching a maximum after three days in the freezing-tolerant rye genotype. There was a continuous increase in the spermine and tyramine contents during the whole acclimation period in the tolerant wheat genotype while nearly constant levels were detected in the sensitive one. The amount of these two amines exhibited a positive correlation with the level of freezing tolerance in each of the five sampling points. Based on the correlations, a coordinated adjustment of the level of the six studied biogenic amines occurred during the acclimation period which could contribute to the efficient adaptation to cold. In addition, the earlier induction of the biogenic amine accumulation in the freezing tolerant genotypes may contribute to their better cold acclimation.

Download Full-text

Effect of disuse on sarcoplasmic reticulum in fast and slow skeletal muscle

AJP Cell Physiology ◽

10.1152/ajpcell.1982.243.3.c156 ◽

1982 ◽

Vol 243 (3) ◽

pp. C156-C160 ◽

Cited By ~ 24

Author(s):

D. H. Kim ◽

F. A. Witzmann ◽

R. H. Fitts

Keyword(s):

Skeletal Muscle ◽

Sarcoplasmic Reticulum ◽

Atpase Activity ◽

Time Course ◽

Vastus Lateralis ◽

Control Level ◽

Type I ◽

Uptake Capacity ◽

Three Samples ◽

Fast Twitch

The effect of 6 wk of hindlimb immobilization on rat skeletal muscle sarcoplasmic reticulum (SR) was determined in the slow-twitch, type I soleus (SOL), the fast-twitch, type IIA deep region of the vastus lateralis (DVL), and the fast-twitch, type IIB superficial region of the vastus lateralis (SVL). Immobilization produced a significant decline in the Ca2+ uptake rate (Vmax) of SR vesicles from the slow SOL (0.930 +/- 0.116 to 0.365 +/- 0.071 mumol Ca2+ . mg-1 . min-1), while the SR Vmax increased in the fast SVL (2.763 +/- 0.133 to 5.209 +/- 0.687) and was unaltered in the DVL. Vesicles from the fast SVL and DVL also exhibited a higher total Ca2+ uptake capacity following immobilization. An evaluation of the time course of the immobilization-mediated effect revealed an increased Ca2+ uptake capacity in all three samples after 1 wk. In the SOL total Ca2+ uptake returned to control level after 2 wk, while in the fast-twitch muscles the higher capacities were maintained. The Ca2+-stimulated SR ATPase activity was not altered in any of the muscles studies, although the total SR ATPase activity increased twofold in the slow SOL.

Download Full-text

Modulation by Ryanodine of Active Calcium Loading and Caffeine Induced Calcium Release of Heavy Sarcoplasmic Reticulum Vesicles

Zeitschrift für Naturforschung C ◽

10.1515/znc-1992-0618 ◽

1992 ◽

Vol 47 (5-6) ◽

pp. 429-439 ◽

Cited By ~ 6

Author(s):

Wilhelm Hasselbach ◽

Andrea Migala

Keyword(s):

Sarcoplasmic Reticulum ◽

Time Course ◽

Calcium Uptake ◽

Calcium Release ◽

Atp Hydrolysis ◽

Storage Period ◽

Calcium Release Channel ◽

Release Channel ◽

Calcium Storage ◽

Active Calcium

The effect of ATP on the calcium release channel in heavy sarcoplasmic reticulum vesicles modulated by ryanodine has been analyzed by monitoring active calcium uptake and caffeine induced calcium release under near physiological conditions. Native as well as ryanodine reacted vesicles display a complex time course of calcium uptake resulting in nearly complete exhaustion of medium calcium when ATP in combination with an ATP-regenerating system, in contrast to ATP alone, or dinitrophenyl phosphate, were used to support calcium uptake. Applying of dinitrophenyl phosphate as energy yielding substrate, not affecting channel activity, allowed to estimate the fraction of light vesicles devoided of calcium channels contam inating the heavy preparation as the fraction that stores calcium after the preparation has been treated with channel opening, low concentrations of ryanodine (1 μᴍ). Calcium uptake by contaminant light vesicles (25%) cannot account for calcium storage, as well as, abolition of caffeine induced calcium release of ryanodine treated heavy vesicles. Calcium uptake of native and ryanodine treated vesicles is accompanied by the uptake of equivalent amounts of inorganic phosphate arising from ATP hydrolysis indicating that calcium is mainly stored as calcium phosphate. The momentary capability of the preparation to accumulate calcium was measured by activating calcium uptake during the calcium storage period with 0.2 mᴍ 45CaCl2 and 4 mᴍ phosphate at short time intervals. A significant increase of the momentary uptake activity with time was observed being more pronounced for ryanodine treated than for native vesicles indicating that under regenerating conditions, ATP can induce closing of the native and even more effectively of the ryanodine modified calcium release channels.

Download Full-text