Abstract：
:Heat rate and tension were measured during the steady state of isovelocity shortening in frog sartorius muscles at two speeds (7.5 and 2.0 mm s-1) through two ranges of the length-tension curve: 1.11 to 1.01 L0 and 1.01 to 0.91 L0. Both heat rate and mechanical power were higher at short length than at long length. The ratio of mechanical power to total energy rate was smaller at short length. The difference in heat rates in the two length ranges was greatest during shortening at 7.5 mm s-1 and least during isometric contractions. Calculations were made for two extreme interpretations of the results, based on the assumption that 30% of the isometric maintenance heat rate at optimum length is produced by processes related to activation: that all the difference in heat rate results from effects of length on activation processes and that all the difference results from effects on contractile processes. The rate of heat production by activation processes would have to be 1.5 times higher at short than at long length in an isometric contraction, 1.7 times higher during shortening at 2mm s-1 and 2.0 times higher at 7.5 mm s-1 to explain the differences in heat rate. The rate of contractile processes would have to be only 1.2 times higher at short than at long length. The results favour the interpretation that the contractile process itself is sensitive to sarcomere length near the plateau of the length-tension curve.(ABSTRACT TRUNCATED AT 250 WORDS)
journal_name
J Muscle Res Cell Motiljournal_title
Journal of muscle research and cell motilityauthors
Gilbert SHdoi
10.1007/BF01753412subject
Has Abstractpub_date
1986-04-01 00:00:00pages
115-21issue
2eissn
0142-4319issn
1573-2657journal_volume
7pub_type
杂志文章abstract：:Clenbuterol is a beta2-adrenoceptor agonist primarily used for treating bronchospasm and alleviating the symptoms of chronic obstructive pulmonary disease (COPD) in the horse. In other species (rats, mice, sheep, and cattle), chronic high doses of clenbuterol (typically in the milligram per kilogram body weight range)...
journal_title：Journal of muscle research and cell motility
pub_type： 杂志文章
doi：10.1023/a:1027377731137
更新日期：2003-01-01 00:00:00
abstract：:Although a substantial literature exists on the in vitro polymerization of purified myosin, little is known about native thick filament assembly, remodeling or turnover. We have recently described a cell-free system (Bouche et al., 1988) to examine the interactions between thick filaments and soluble, newly synthesize...
journal_title：Journal of muscle research and cell motility
pub_type： 杂志文章
doi：10.1007/BF01774035
更新日期：1991-04-01 00:00:00
abstract：:Following activation by G-protein-coupled receptor agonists, protein kinase C (PKC) modulates cardiac myocyte function by phosphorylation of intracellular targets including myofilament proteins cardiac troponin I (cTnI) and cardiac myosin binding protein C (cMyBP-C). Since PKC phosphorylation has been shown to decreas...
journal_title：Journal of muscle research and cell motility
pub_type： 杂志文章
doi：10.1007/s10974-012-9294-9
更新日期：2012-12-01 00:00:00
abstract：:Effects of Mn2+ and Ca2+ on the mechanical properties of glycerinated myofibrillar bundles originating from slow S1 type muscle fibres of superficial flexor muscles of the lobster Nephrops norvegicus were investigated. Mn2+ (5-20 microM) activated the preparations in a dose-dependent manner. The sensitivity of myofibr...
journal_title：Journal of muscle research and cell motility
pub_type： 杂志文章
doi：10.1023/a:1005312610629
更新日期：1998-06-01 00:00:00
abstract：:While the migration of capillary endothelial cells is believed central to the process of new blood vessel development in vivo, the biochemical basis for endothelial motility is unknown. Herein, we demonstrate that retina-derived growth factor (RDGF), a mitogen for endothelial cells (EC), stimulates the migration of mi...
journal_title：Journal of muscle research and cell motility
pub_type： 杂志文章
doi：10.1007/BF00713928
更新日期：1984-12-01 00:00:00
abstract：:The properties of spin-labelled myosin, prepared from rabbit skeletal and scallop adductor muscle, on forming a long-lived complex with ADP and vanadate (M.ADP.Vi), have been investigated. In the case of an iodoacetamide-based label attached to rabbit myosin or subfragment 1, M.ADP.Vi formation is characterized by a m...
journal_title：Journal of muscle research and cell motility
pub_type： 杂志文章
doi：10.1007/BF00713154
更新日期：1984-02-01 00:00:00
abstract：:Myosin heavy chain kinase activity was identified in the high speed supernate of lysed Dictyostelium amoebae and was precipitated by 30-50% ammonium sulphate. In low ionic strength buffer, the activity bound tightly to a Cibacron Blue Sepharose column and eluted as a single peak with 1.0 M NaCl. Gel filtration chromat...
journal_title：Journal of muscle research and cell motility
pub_type： 杂志文章
doi：10.1007/BF01753566
更新日期：1986-12-01 00:00:00
abstract：:Protein kinase C (PKC) is known to play important roles in integrin mediated cell spreading. This study investigated the role of PKC during insulin mediated muscle cell spreading, which was independent of integrin alpha5. We found that PKC-alpha becomes active and localise to membrane during insulin mediated cell spre...
journal_title：Journal of muscle research and cell motility
pub_type： 杂志文章
doi：10.1023/a:1022028808806
更新日期：2002-01-01 00:00:00
abstract：:We determined the effects of epigallocatechin-3-gallate (EGCG) and epicatechin (EC), on pump turnover and Ca2+ transport by the cardiac form of the sarcoplasmic/endoplasmic reticulum Ca2+-ATPase (SERCA). Fluorescence spectroscopy was used to directly measure SERCA ATPase activity and to measure Ca2+ uptake into cardia...
journal_title：Journal of muscle research and cell motility
pub_type： 杂志文章
doi：10.1007/s10974-011-9256-7
更新日期：2011-09-01 00:00:00
abstract：:Critical illness myopathy (CIM) is associated with severe muscle atrophy and fatigue in affected patients. Apoptotic signaling is involved in atrophy and is elevated in muscles from patients with CIM. In this study we investigated underlying mechanisms of apoptosis-related pathways in muscles with different fiber type...
journal_title：Journal of muscle research and cell motility
pub_type： 杂志文章
doi：10.1007/s10974-015-9410-8
更新日期：2015-06-01 00:00:00
abstract：:Skeletal muscle repair requires the migration of myoblasts (activated satellite cells) both to the injury site and then within the wound to facilitate cellular alignment in preparation for differentiation, fusion and eventual healing. Along this journey, the cells encounter a range of soluble and extracellular matrix ...
journal_title：Journal of muscle research and cell motility
pub_type： 杂志文章,评审
doi：10.1007/s10974-013-9364-7
更新日期：2013-12-01 00:00:00
abstract：:We have determined the amino acid sequences of the essential light chains (ELC) and regulatory light chains (RLC) of myosin from two species of clam, Mercenaria mercenaria and Macrocallista nimbosa, using protein chemistry methods. The N-termini of all four proteins were blocked, and sequencing was carried out on vari...
journal_title：Journal of muscle research and cell motility
pub_type： 杂志文章
doi：10.1007/BF01738587
更新日期：1991-08-01 00:00:00
abstract：:The myosin light chains of slow muscles from different species have been examined two-dimensional gel electrophoresis. While the myosin light chain 2S of mammalian soleus muscles (rabbit, rat and guinea-pig) could not be distinguished from that of avian anterior latissimus dorsi (chicken and turkey), the 1S light chai...
journal_title：Journal of muscle research and cell motility
pub_type： 杂志文章
doi：10.1007/BF00713271
更新日期：1981-09-01 00:00:00
abstract：:The regulated assembly of actin filaments is essential in nearly all cell types. Studying actin assembly dynamics can pose many technical challenges. A number of these challenges can be overcome by using microfluidics to observe and manipulate single actin filaments under an optical microscope. In particular, microflu...
journal_title：Journal of muscle research and cell motility
pub_type： 杂志文章
doi：10.1007/s10974-019-09564-4
更新日期：2020-03-01 00:00:00
abstract：:We found that the active tension of C2C12 myotubes that had been subjected to artificial exercise for ~10 days decreased rapidly after termination of the artificial exercise. When differentiated C2C12 myotubes were subjected to continuous 1 Hz artificial exercise for ~10 days, the active tension increased to ~4× compa...
journal_title：Journal of muscle research and cell motility
pub_type： 杂志文章
doi：10.1007/s10974-010-9230-9
更新日期：2010-12-01 00:00:00
abstract：:Previous studies have shown that lengthening contractions, in contrast to isometric contractions, readily result in sustained malfunctioning of the exercised muscles. The present study was performed to investigate whether an exercise period with many (240) lengthening contractions (LC) results in alterations in muscle...
journal_title：Journal of muscle research and cell motility
pub_type： 杂志文章
doi：10.1023/a:1005345603882
更新日期：1998-05-01 00:00:00
abstract：:Actin filaments are major components of the cytoskeleton in eukaryotic cells and are involved in vital cellular functions such as cell motility and muscle contraction. Tmod and TM are crucial constituents of the actin filament network, making their presence indispensable in living cells. Tropomyosin (TM) is an alpha-h...
journal_title：Journal of muscle research and cell motility
pub_type： 杂志文章,评审
doi：10.1007/s10974-013-9349-6
更新日期：2013-08-01 00:00:00
abstract：:There is evidence to suggest that 8 nm calcium transport particles in the sarcoplasmic reticulum are involved in the regulation of twitch properties in adult muscles. We have studied ultrastructural characteristics of the sarcoplasmic reticulum in relation to previously defined physiological changes that take place in...
journal_title：Journal of muscle research and cell motility
pub_type： 杂志文章
doi：10.1007/BF01753413
更新日期：1986-04-01 00:00:00
abstract：:Small but statistically significant shifts (hysteresis) between the up (increasing tension direction) and down (decreasing tension) pCa/tension relation for several muscle types of the rabbit and rat were found. The largest shift is, at most, 0.093 p units or 60% of that reported for the barnacle muscle. The direction...
journal_title：Journal of muscle research and cell motility
pub_type： 杂志文章
doi：10.1007/BF00713061
更新日期：1985-04-01 00:00:00
abstract：:The L-type Ca2+ channel in skeletal muscle (alpha1S) is essential for excitation-contraction (EC) coupling. Previous studies using chimeras composed of alpha1S together with alpha1C or alpha1M demonstrated the importance of the alpha1S II-III loop and of a smaller subdomain (residues 720-764; 'ECC') in skeletal EC cou...
journal_title：Journal of muscle research and cell motility
pub_type： 杂志文章
doi：10.1023/a:1024830132118
更新日期：2003-01-01 00:00:00
abstract：:The effect of changes in hydrostatic pressure (up to 10 MPa) on the maximally calcium-activated tension in glycerinated rabbit psoas fibres has been examined. The steady active tension was depressed by 0.8% per MPa pressure rise. This pressure sensitivity was enhanced by the pressure of millimolar phosphate and depres...
journal_title：Journal of muscle research and cell motility
pub_type： 杂志文章
doi：10.1007/BF01739967
更新日期：1989-04-01 00:00:00
abstract：:The time course of shortening at zero load was studied by the slack test method during tetanic contractions in isolated, single, slow muscle fibres of the crayfish. In 28 of 32 shortenings (from 14 different fibres) a biphasic shortening was seen, which consisted of an initial high-velocity phase lasting 3.3-20.8 ms a...
journal_title：Journal of muscle research and cell motility
pub_type： 杂志文章
doi：10.1007/BF01738251
更新日期：1992-12-01 00:00:00
abstract：:Cleavage of vertebrate muscle tropomyosin by bacterial Omp T produces an amino-terminally truncated product (residues 7-284). The proteolysed protein, which is resolved from the parent by electrophoresis in the presence of sodium dodecylsulphate, can be generated from a variety of striated and smooth muscle tropomyosi...
journal_title：Journal of muscle research and cell motility
pub_type： 杂志文章
doi：10.1007/s10974-007-9114-9
更新日期：2007-01-01 00:00:00
abstract：:The fine structure of leech body wall muscles, has been analysed under great length variations. All the measurable parameters of the fibre (distance between thick filaments, sarcomere and A band width, percentage of actin crowns around myosin filaments, fibre radius) at different elongations were tested with equations...
journal_title：Journal of muscle research and cell motility
pub_type： 杂志文章
doi：10.1007/BF00711915
更新日期：1985-10-01 00:00:00
abstract：:The optimal utilization of energy substrates in muscle fibers is of primary importance for muscle contraction and whole body physiology. This study aimed to investigate the age-related changes in some indicators of glucose catabolism and fatty acid oxidation in muscles of growing rabbits. Longissimus lumborum (fast-tw...
journal_title：Journal of muscle research and cell motility
pub_type： 杂志文章
doi：10.1007/s10974-004-2768-7
更新日期：2004-01-01 00:00:00
abstract：:Mechanical properties of myofibrillar bundles from single chemically skinned fibres from the superficial abdominal flexor muscle of the Norway lobster Nephrops norvegicus were measured, and the protein content of these fibres was analysed by SDS-PAGE. Two slow fibre phenotypes (S1, S2) were distinguished on the basis ...
journal_title：Journal of muscle research and cell motility
pub_type： 杂志文章
doi：10.1023/a:1005481725344
更新日期：1999-04-01 00:00:00
abstract：:Skeletal muscle fibers exhibit plasticity of their physiological and biochemical properties in response to the firing pattern from the innervating motor neuron. In particular, the gene expression pattern generally characteristic of a slow twitch fiber can be induced in a fast twitch fiber by chronic slow fiber type el...
journal_title：Journal of muscle research and cell motility
pub_type： 杂志文章,评审
doi：10.1007/s10974-006-9080-7
更新日期：2006-01-01 00:00:00
abstract：:Cardiac muscle M-band structures in several mammals (guinea pig, rabbit, rat and cow) and also from three teleosts (plaice, carp and roach), have been studied using electron microscopy and image processing. Axial structure seen in negatively stained isolated myofibrils or negatively stained cryo-sections shows the pre...
journal_title：Journal of muscle research and cell motility
pub_type： 杂志文章
doi：10.1007/BF00121071
更新日期：1994-12-01 00:00:00
abstract：:The change in orientation of myosin crossbridges in contracting muscle during sudden length changes was examined by fluorescence polarization. This study used a fluorescent ATP analogue, 1,N6-etheno-2-aza-ATP(epsilon-2-aza-ATP) as a probe. Its fluorescence is considerably enhanced upon binding with myosin and is depen...
journal_title：Journal of muscle research and cell motility
pub_type： 杂志文章
doi：10.1007/BF00712310
更新日期：1985-02-01 00:00:00
abstract：:The term 'microtubule dynamics' is often used to describe assembly/disassembly characteristics of this important cytoskeletal polymer. The ability to image microtubules in live Dictyostelium cells has revealed additional dynamic components, acting on the individual assembled tubules. At least two separate forces are i...
journal_title：Journal of muscle research and cell motility
pub_type： 杂志文章,评审
doi：10.1023/a:1024446821701
更新日期：2002-01-01 00:00:00
