Abstract:
:MagFluo-4 fluorescence (Ca2+) transients associated with action potentials were measured in intact muscle fibres, manually dissected from toads ( Leptodactylus insularis ) or enzymatically dissociated from mice. In toads, the decay phase of the Ca2+ transients is described by a single exponential with a time constant ( tau ) of about 7 ms. In mice, a double exponential function with tau 's of 1.5 and 15.5 ms, respectively gives a better fit. In both species the amplitude of Ca2+ transients diminished during repetitive stimulation: in amphibian muscle fibres, the decrease was about 20% with 1 Hz stimulation and 55% at 10 Hz. In mammalian fibres, repetitive stimulation causes a less conspicuous decrease of the transient amplitude: 10% at 1 Hz and 15% at 10 Hz. During tetanic stimulation at 100 Hz the transient amplitude decays to 20% in toad fibres and 40% in mouse fibres. This decrease could be associated with the phenomenon of inactivation of Ca2+ release, described by other authors. Recovery from inactivation, studied by a double stimuli protocol also indicates that in toad fibres the ability to release Ca2+ is abolished to a greater extent than in mouse fibres. In fact the ratio between the amplitudes of the second and first transient, when they are separated by a 10 ms interval, is 0.29 for toad and 0.58 for mouse fibres. In toad fibres, recovery from inactivation, to about 80 % of the initial value, occurs with a tau of 32 ms at 22 degrees C; while in mouse fibres recovery from inactivation is almost complete and occurs with a tau of 36 ms under the same conditions. The results indicate that Ca2+ release in enzymatically dissociated mammalian muscle fibres inactivates to a smaller extent than in intact amphibian muscle fibres.
journal_name
J Muscle Res Cell Motiljournal_title
Journal of muscle research and cell motilityauthors
Caputo C,Bolaños P,Gonzalez Adoi
10.1007/s10974-004-4071-zkeywords:
subject
Has Abstractpub_date
2004-01-01 00:00:00pages
315-28issue
4-5eissn
0142-4319issn
1573-2657pii
5274071journal_volume
25pub_type
杂志文章abstract::The organization of the principal cytoskeletal components (actin, tubulin and 10 nm filament protein) have been compared by immunofluorescence microscopy in two populations of chick heart fibroblasts, previously shown to be adapted respectively for rapid, directed migration or adhesion and growth. We find that neither...
journal_title:Journal of muscle research and cell motility
pub_type: 杂志文章
doi:10.1007/BF00711922
更新日期:1980-03-01 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::Full muscle relaxation happens when [Ca2+] falls below the threshold for force activation. Several experimental models, from whole muscle organs and intact muscle down to skinned fibers, have been used to explore the cascade of kinetic events leading to mechanical relaxation. The use of single myofibrils together with...
journal_title:Journal of muscle research and cell motility
pub_type: 杂志文章
doi:10.1007/s10974-019-09566-2
更新日期:2019-11-19 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::To date, there has been no report of rat TnC purification, despite the rat being an animal commonly used in physiological studies of mammalian muscle. In this study we isolated the fast and slow Troponin C isoforms from rat extensor digitorum longus (23 microg TnC/g wet weight) and soleus (17.6 microg TnC/g wet weight...
journal_title:Journal of muscle research and cell motility
pub_type: 杂志文章
doi:10.1023/b:jure.0000009896.78385.16
更新日期:2003-01-01 00:00:00
abstract::Two single mutations, R694N and E45Q, were introduced in the beta isoform of human cardiac myosin to remove permanent salt bridges E45:R694 and E98:R694 in the SH1-SH2 helix of the myosin head. Beta isoform-specific bridges E45:R694 and E98:R694 were discovered in the molecular dynamics simulations of the alpha and be...
journal_title:Journal of muscle research and cell motility
pub_type: 杂志文章
doi:10.1007/s10974-020-09588-1
更新日期:2020-09-14 00:00:00
abstract::Extensor digitorum longus muscles of normal mice (C57BL/10ScSn hereafter called C57) were orthotopically transplanted into dystrophin-deficient mice (mdx) and reciprocally, mdx Extensor digitorum longus muscles were transplanted into C57 mice. After an initial phase of degeneration, transplanted muscles regenerate nea...
journal_title:Journal of muscle research and cell motility
pub_type: 杂志文章
doi:10.1007/BF00140322
更新日期:1996-02-01 00:00:00
abstract::The aim of the study was to investigate sex-related differences in contractile properties, parameters of action potentials, and mechanisms of force regulation of motor units in the rat soleus muscle, which is a frequent experimental model in animal research. It was revealed that the mean mass of the muscle in males wa...
journal_title:Journal of muscle research and cell motility
pub_type: 杂志文章
doi:10.1007/s10974-015-9408-2
更新日期:2015-06-01 00:00:00
abstract::Skeletal muscle hypertrophy is a result of increased load, such as functional and stretch-overload. Activation of satellite cells and proliferation, differentiation and fusion are required for hypertrophy of overloaded skeletal muscles. On the contrary, a dramatic loss of skeletal muscle mass determines atrophy settin...
journal_title:Journal of muscle research and cell motility
pub_type: 杂志文章,评审
doi:10.1007/s10974-010-9204-y
更新日期:2009-12-01 00:00:00
abstract::Proteins containing disintegrin domains play a variety of roles in regulating processes involving adhesion, migration and cell type specification during development of many metazoan organisms. Most disintegrin domain containing proteins belong to the ADAM (a disintegrin and a metalloprotease) family of proteins that a...
journal_title:Journal of muscle research and cell motility
pub_type: 杂志文章,评审
doi:10.1023/a:1024440014857
更新日期:2002-01-01 00:00:00
abstract::Myosin has been purified from chicken pectoralis muscle at various stages of development, from 10 days' incubation to approximately 10 months after hatching. Embryonic myosin from the earliest stage showed a high level of ATPase activity, similar to that obtained for adult pectoralis myosin. Two-dimensional peptide ma...
journal_title:Journal of muscle research and cell motility
pub_type: 杂志文章
doi:10.1007/BF00712161
更新日期:1983-12-01 00:00:00
abstract::A transducer has been developed for measuring the minute forces generated during isometric contractions (1.0-10.0 microN) of single smooth muscle cells from the pig urinary bladder and the human uterus. In addition to its high sensitivity, resolution and stability (100 mV microN-1, and less than 0.1 microN and less th...
journal_title:Journal of muscle research and cell motility
pub_type: 杂志文章
doi:10.1007/BF01766671
更新日期:1990-08-01 00:00:00
abstract::Appropriate organization of cytoskeletal components are required for normal distribution and intracellular localization of different ion channels and proteins involved in calcium homeostasis, signal transduction, and contractile function of striated muscle. Proteins of the contractile system are in direct or indirect ...
journal_title:Journal of muscle research and cell motility
pub_type: 杂志文章
doi:10.1007/s10974-020-09573-8
更新日期:2020-01-18 00:00:00
abstract::Isolated fibres from various muscles were skinned mechanically in oil. From a Ca2+-loaded micropipette, local applications of Ca2+ were made. These produced a limited contraction which relaxed spontaneously. The time-course of sarcomere shortening and re-lengthening was recorded by microcinephotography. Application of...
journal_title:Journal of muscle research and cell motility
pub_type: 杂志文章
doi:10.1023/a:1018603032590
更新日期:1997-08-01 00:00:00
abstract::White muscle fibres from dogfish were used to compare the energetic costs of shortening by fully active muscle and by relaxing muscle. The muscle preparation was tetanized for 0.6 s and shortened either during stimulation or during relaxation. The distance shortened was 1 mm (about 15% L0, the muscle length optimum fo...
journal_title:Journal of muscle research and cell motility
pub_type: 杂志文章
doi:10.1023/a:1005455505056
更新日期:1998-10-01 00:00:00
abstract::The distribution of Ca2+ and Mg2+ among the 'regulatory' cation binding sites of troponin (T-sites) and the strong, Ca2+-Mg2+ binding sites of troponin and parvalbumins (P-sites) in the sarcoplasm of a muscle was calculated. At rest, 60% of the T-sites were metal free, while 92% of the P-sites were loaded with Mg2+. I...
journal_title:Journal of muscle research and cell motility
pub_type: 杂志文章
doi:10.1007/BF00712090
更新日期:1982-12-01 00:00:00
abstract::The pattern of spontaneous skeletal muscle degeneration and clinical recovery hindlimb muscles of the mdx mutant mouse was examined for functional and metabolic confirmation of apparent structural regeneration. The contractile properties, histochemical staining and myosin light chain and parvalbumin contents of extens...
journal_title:Journal of muscle research and cell motility
pub_type: 杂志文章
doi:10.1007/BF01738755
更新日期:1988-12-01 00:00:00
abstract::Tropomyosins (Tm) in humans are expressed from four distinct genes and by alternate splicing >40 different Tm polypeptide chains can be made. The functional Tm unit is a dimer of two parallel polypeptide chains and these can be assembled from identical (homodimer) or different (heterodimer) polypeptide chains provided...
journal_title:Journal of muscle research and cell motility
pub_type: 杂志文章,评审
doi:10.1007/s10974-013-9353-x
更新日期:2013-08-01 00:00:00
abstract::The sarcomere length (SL) dependence of the calcium sensitivity of force was measured in skinned single twitch and slow-tonic muscle fibres from frog and toad. Twitch and slow-tonic fibres were characterized by location, appearance, physiological response to calcium and by protein band patterns from sodium-dodecyl-sul...
journal_title:Journal of muscle research and cell motility
pub_type: 杂志文章
doi:10.1007/BF00132181
更新日期:1993-02-01 00:00:00
abstract::Our current understanding of the structure of the thin filaments of muscle and the molecular mechanism by which thin filaments regulate muscle contraction are reviewed and discussed. We focus, in particular, on the crucial role played by Jean Hanson in these studies and on later contributions from those whose work she...
journal_title:Journal of muscle research and cell motility
pub_type: 传,历史文章,杂志文章,评审
doi:10.1007/s10974-004-3148-z
更新日期:2004-01-01 00:00:00
abstract::Muscle development involves a complex sequence of time and spatially regulated cellular events leading to the formation of highly specialised syncytial muscle cells displaying a common feature, the capacity of contraction. Analyses of mechanisms controlling muscle development reveals that the main steps of muscle form...
journal_title:Journal of muscle research and cell motility
pub_type: 杂志文章,评审
doi:10.1007/s10974-008-9133-1
更新日期:2007-01-01 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::The mechanical events following release of ATP from P3-1-(2-nitro)phenylethyladenosine-5'-triphosphate (caged-ATP) in skinned guinea pig taenia coli smooth muscle in rigor were investigated. A rigor force of about 25-35% of the maximal active force was obtained by removing ATP at the plateau of a maximal active contra...
journal_title:Journal of muscle research and cell motility
pub_type: 杂志文章
doi:10.1007/BF01578427
更新日期:1987-10-01 00:00:00
abstract::To study the development of muscle-specific features during myogenesis, we analysed the ultrastructure and voltage-dependent currents of frog embryonic skeletal myocytes maintained in culture for 10 days. The cells were maintained under culture conditions that prevented cell division, fusion and cell contacts with neu...
journal_title:Journal of muscle research and cell motility
pub_type: 杂志文章
doi:10.1023/a:1005506216009
更新日期:1999-08-01 00:00:00
abstract::Gaps in our understanding of muscle mechanics demonstrate that the current model is incomplete. Increasingly, it appears that a role for titin in active muscle contraction might help to fill these gaps. While such a role for titin is increasingly accepted, the underlying molecular mechanisms remain unclear. The goals ...
journal_title:Journal of muscle research and cell motility
pub_type: 杂志文章
doi:10.1007/s10974-019-09540-y
更新日期:2020-03-01 00:00:00
abstract::Cells isolated from pig urinary bladders and pregnant full term human uteruses were attached longitudinally between a microforce transducer and a length displacement apparatus. Cells were stretched by applying a series of ramp-like length changes of 0.2 s duration and 10.0 microns amplitude at intervals of 15 min. Pas...
journal_title:Journal of muscle research and cell motility
pub_type: 杂志文章
doi:10.1007/BF01739765
更新日期:1990-10-01 00:00:00
abstract::CapZ is a widely distributed and highly conserved, heterodimeric protein, that nucleates actin polymerization and binds to the barbed ends of actin filaments, preventing the addition or loss of actin monomers. CapZ interaction with actin filaments was shown to be of high affinity and decreased in the presence of PIP2....
journal_title:Journal of muscle research and cell motility
pub_type: 杂志文章
doi:10.1023/a:1005489319058
更新日期:1999-02-01 00:00:00
abstract::The loss of muscle force and power during fatigue from intense contractile activity is associated with, and likely caused by, elevated levels of phosphate ([Formula: see text]) and hydrogen ions (decreased pH). To understand how these deficits in muscle performance occur at the molecular level, we used direct measurem...
journal_title:Journal of muscle research and cell motility
pub_type: 杂志文章
doi:10.1007/s10974-018-9499-7
更新日期:2018-08-01 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::Cytokinesis is the mechanical process that allows the simplest unit of life, the cell, to divide, propagating itself. To divide, the cell converts chemical energy into mechanical energy to produce force. This process is thought to be active, due in large part to the mechanochemistry of the myosin-II ATPase. The cell's...
journal_title:Journal of muscle research and cell motility
pub_type: 杂志文章,评审
doi:10.1023/a:1024419510314
更新日期:2002-01-01 00:00:00