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 and a following slow-velocity phase lasting for the entire time examined (up to 89.2 ms). Provided that the shortening occurred uniformly along the fibre length, velocity in the initial phase, V1, of the biphasic shortening was 14.4 +/- 3.4 (mean +/- SD, n = 10) microns s-1 per half sarcomere at Lo, the slack length, at 20 degrees C, while that in the second phase, V2, was 7.4 +/- 1.4 microns s-1 per half sarcomere. Lowering temperature decreased both V1 and V2 with Q10 = 1.4 for V1 and 2.0 for V2. Lowering the external Ca concentration from 15 mM, the standard, to 2 mM resulted in a tetanic tension below one-third of that at 15 mM Ca and decreased both V1 (t test; p < 0.01) and V2 (p < 0.001). Prestretching the fibre to 1.5 Lo had no significant effect on V2 (p < 0.3) but increased V1 (p < 0.001). The distance shortened during the initial high-velocity phase, LV1, was 4.0 +/- 1.8% Lo (mean +/- SD, n = 10) at 20 degrees C or about 0.14 microns per half sarcomere on average. LV1 was independent of the tetanic tension level when it was changed by lowering the external Ca concentration or temperature in the same fibre. Prestretching the fibre to 1.5 Lo, at which the sum of the active and the resting tension was lower than Po at Lo in two of three fibres, increased LV1 significantly (p < 0.001). The independency of LV1 from the tension level indicates that the initial high-velocity phase was not from shortening of some inert components in the fibre. One possibility is that the initial high-velocity phase was brought about by an acceleration of shortening by a compressive force, the origin of which has been discussed. The slow-velocity phase seemed to result from the crossbridge turnover with little exogeneous stress on myofilaments. Four different fibres exhibited an unloaded shortening with a constant velocity during the entire time examined (29.9-61.8 ms). This type of shortening had a velocity between the usual V1 and V2 values, suggesting that a compressive force accelerated the shortening during the entire time.
journal_name
J Muscle Res Cell Motiljournal_title
Journal of muscle research and cell motilityauthors
Tameyasu Tdoi
10.1007/BF01738251keywords:
subject
Has Abstractpub_date
1992-12-01 00:00:00pages
619-29issue
6eissn
0142-4319issn
1573-2657journal_volume
13pub_type
杂志文章abstract::To explain observed differences in the activation dependence of force redevelopment kinetics between cardiac and skeletal muscle, two numerical models of contractile regulation by Ca2+ were investigated. Ca2+ binding and force production were each modelled as two-state processes with forward and reverse rate constants...
journal_title:Journal of muscle research and cell motility
pub_type: 杂志文章
doi:10.1023/a:1018635907091
更新日期:1997-12-01 00:00:00
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 ...
journal_title:Journal of muscle research and cell motility
pub_type: 杂志文章
doi:10.1007/s10974-004-4071-z
更新日期:2004-01-01 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 mRNA levels of the adult and the neonatal sarcoplasmic/endoplasmic reticulum Ca(2+)-ATPases (SERCA1a and SERCA1b, respectively) and those of the muscle regulatory factors (MRFs: myoD, myf-5, myogenin, MRF4) have been assessed by RT PCR in rat soleus muscles immobilized for 3 days in an extended position (passive s...
journal_title:Journal of muscle research and cell motility
pub_type: 杂志文章
doi:10.1023/a:1005541522599
更新日期:1999-05-01 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::RNA-binding motif protein 3 (RBM3), a stress-inducible RNA-binding protein that increases protein synthesis and confers cell protection in multiple cell types, has been identified as a possible regulator of skeletal muscle mass. Therefore, the primary aim of this study was to examine the impact of elevated RBM3 on ske...
journal_title:Journal of muscle research and cell motility
pub_type: 杂志文章
doi:10.1007/s10974-018-9496-x
更新日期:2018-04-01 00:00:00
abstract::In this study the spontaneous activities of prescapular lymph nodes, which were isolated from calves, goats and sheep and mesenteric lymph nodes of guinea-pigs were recorded and analysed in the frequency domain. Stretch-evoked contractions of the mesenteric lymph nodes were also recorded and their frequency characteri...
journal_title:Journal of muscle research and cell motility
pub_type: 杂志文章
doi:10.1007/BF00711961
更新日期:1983-02-01 00:00:00
abstract::The in vivo state of assembly of myosin in vertebrate smooth muscle is controversial. In vitro studies on purified smooth muscle myosin show that it is monomeric (10S) under relaxing conditions and filamentous under contraction conditions. Electron microscopic and antibody labelling studies of intact smooth muscles, o...
journal_title:Journal of muscle research and cell motility
pub_type: 杂志文章
doi:10.1023/a:1018634412117
更新日期:1997-06-01 00:00:00
abstract::The effect of Ca2+ activation on the apparent rate constant governing the dissociation of force generating myosin crossbridges was studied in skinned rabbit adductor magnus fibres (fast-twitch) at 21 +/- 1 degree C. Simultaneous measurements of Ca2(+)-activated isometric force and ATPase activity were conducted in par...
journal_title:Journal of muscle research and cell motility
pub_type: 杂志文章
doi:10.1007/BF01781174
更新日期:1991-02-01 00:00:00
abstract::The cellular function of the giant protein titin in striated muscle is a major focus of scientific attention. Particularly, its role in passive mechanics has been extensively investigated. In strong contrast, the structural details of this filament are very poorly understood. To date, only a handful of atomic models f...
journal_title:Journal of muscle research and cell motility
pub_type: 杂志文章
doi:10.1007/s10974-005-9017-6
更新日期:2005-01-01 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::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::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::Hodges and his colleagues identified a 12 amino acid fragment of troponin I (TnI-ip) that inhibits Ca(2+)-activated force and reduces the effectiveness Ca(2+) as an activator. To understand the role of troponin C (TnC) in the extended cooperative interactions of thin filament activation, we compared the effect of TnI-...
journal_title:Journal of muscle research and cell motility
pub_type: 杂志文章
doi:10.1007/s10974-013-9336-y
更新日期:2013-05-01 00:00:00
abstract::temporaria (0.9-2.5degrees C) were stimulated to produce a 1 s isometric tetanus at regular intervals until constant mechanical responses were attained. Various degrees of force depression ("fatigue") were produced by decreasing the contraction interval from 30 or 15 min (control to 120, 60, 30 and 15s, respectively. ...
journal_title:Journal of muscle research and cell motility
pub_type: 杂志文章
doi:10.1007/BF00713270
更新日期:1981-09-01 00:00:00
abstract::Isolated frog muscle fibres of four different lengths (L0, initial; L1, 15%; L2, 25%; and L3, 35% stretched vs. L0) were stimulated continuously (3 min) by suprathreshold rectangular pulses at three different frequencies (f1 = 5 Hz, f2 = 6.7 Hz and f3 = 10 Hz). Using a pair of electrodes mounted at a fixed distance, t...
journal_title:Journal of muscle research and cell motility
pub_type: 杂志文章
doi:
更新日期:1998-01-01 00:00:00
abstract::Single twitch muscle fibres have been isolated from various parts of the iliofibularis muscle of Xenopus laevis. After measurements of their isotonic contractile properties, myosin extraction was performed on individual fibres and the extract analysed by various forms of gel electrophoresis. In agreement with previous...
journal_title:Journal of muscle research and cell motility
pub_type: 杂志文章
doi:10.1007/BF01574594
更新日期:1987-06-01 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::We investigated the regulatory roles of MgADP and free Ca2+ in isometric tension development in skinned bovine cardiac muscle. We found that, in the relaxed state without free Ca2+, MgADP elicited a sigmoidal increase in active tension, as is the case in skeletal muscle (ADP-contraction). The critical MgADP concentrat...
journal_title:Journal of muscle research and cell motility
pub_type: 杂志文章
doi:10.1023/a:1005437517287
更新日期:1998-11-01 00:00:00
abstract::The hypothesis that calmodulin (CaM) may act as a positive modulator of junctional SR Ca2+-release channel/ ryanodine receptor (RyRl) rests largerly on the demonstrated capacity of CaM to interact structurally and functionally with RyRl at pCa > 8 (Tripathy et al., 1995). The goal of the present [3H]-ryanodine binding...
journal_title:Journal of muscle research and cell motility
pub_type: 杂志文章
doi:10.1023/a:1005635330773
更新日期:2000-01-01 00:00:00
abstract::Skeletal muscle tissue is mechanosensitive, as it is able to sense mechanical impacts and to translate these into biochemical signals making the tissue adapt. Among its mechanosensitive nature, skeletal muscle tissue is the largest metabolic organ of the human body. Disturbances in skeletal muscle mechanosensing and m...
journal_title:Journal of muscle research and cell motility
pub_type: 杂志文章,评审
doi:10.1007/s10974-017-9489-1
更新日期:2017-08-01 00:00:00
abstract::The length dependency of the sensitivity to activators of the smooth muscle of different blood vessels is not yet fully understood. Muscle preparations of the aorta, the femoral artery and the portal vein of the rabbit were investigated for the length dependency of the sensitivity to phenylephrine and calcium in both ...
journal_title:Journal of muscle research and cell motility
pub_type: 杂志文章
doi:10.1023/a:1005408015885
更新日期:1999-01-01 00:00:00
abstract::High speed isovelocity shortening using a servo-controlled lever was performed on isolated whole frog sartorius muscles at long lengths to ensure substantial passive tension. The tension records of unstimulated control experiments were subtracted from the tension records of fully-tetanized experiments on the same musc...
journal_title:Journal of muscle research and cell motility
pub_type: 杂志文章
doi:10.1007/BF00123833
更新日期:1994-02-01 00:00:00
abstract::The width (D) and the 1,0 lattice spacing (d1,0) at various ionic compositions of mechanically skinned single fibres (from semitendinosus muscle of Rana catesbeiana) were measured at various concentrations of polyvinyl pyrrolidone (PVP K-30, Mn = 40 000) from 0 to 6% at 20 degrees C. In a standard relaxing solution (4...
journal_title:Journal of muscle research and cell motility
pub_type: 杂志文章
doi:10.1007/BF01753558
更新日期:1986-06-01 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::The myosin II motor from Dictyostelium discoideum has been engineered to contain single tryptophan residues at strategic locations to probe movements of switch 1 and switch 2. The tryptophan residue at W501 probes movement of the relay helix and indirectly reports on switch 2 movement. This probe suggests that there i...
journal_title:Journal of muscle research and cell motility
pub_type: 杂志文章,评审
doi:10.1007/s10974-005-9004-y
更新日期:2005-01-01 00:00:00
abstract::We examined the tension responses induced by rapid temperature-jumps (T-jumps) applied at different times during twitch and tetanic contractions in small intact fibre bundles (5-10 fibres) isolated from a fast foot muscle (flexor hallucis brevis) of the rat. A rapid T-jump of 2-4 degrees C was induced by a 0.2 ms infr...
journal_title:Journal of muscle research and cell motility
pub_type: 杂志文章
doi:10.1007/s10974-005-4568-0
更新日期:2005-01-01 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::Changes in the isoform patterns of myosin heavy chains (MHC) and Ca2+-ATPase (SERCA) were studied in long-term (72 days) denervated slow-twitch soleus muscles of euthyroid and hyperthyroid rabbits. MHC isoforms were separated electrophoretically. SERCA isoforms were assessed by electrophoretic separation of the trypsi...
journal_title:Journal of muscle research and cell motility
pub_type: 杂志文章
doi:10.1023/a:1014543507149
更新日期:2001-01-01 00:00:00
abstract::The kinetics of smooth muscle are thought to be partially determined by the level of the expression of the 7 amino acid insert, SMB, in the myosin heavy chain, as SMB is generally expressed at higher levels in faster smooth muscle. In this study, we determined the role of this insert on shortening velocity and force r...
journal_title:Journal of muscle research and cell motility
pub_type: 杂志文章
doi:10.1023/b:jure.0000035879.87045.4b
更新日期:2004-01-01 00:00:00