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  1. 82 Acta Neurobiologiae Experimentalis
  2. 10 Journal of Physiology and Pharmacology
  3. 3 Biocybernetics and Biomedical Engineering
  4. 2 Studies in Physical Culture and Tourism
  5. 1 Acta Physiologica Polonica
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  1. 4 2019
  2. 7 2017
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  4. 6 2015
  5. 12 2013
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  1. 98 Celichowski J.
  2. 36 Krutki P.
  3. 20 Drzymala-Celichowska H.
  4. 18 Lochynski D.
  5. 14 Grottel K.
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1
Content available remote The tetanic depression in unfused tetani of fast motor units in mammalian muscle
100%
Celichowski J.
Biocybernetics and Biomedical Engineering
|
2005
|
tom Vol. 25, no. 4
27-35
EN
Tetanic depression is a phenomenon that limits the force of unfused tetani in contractions evoked at unstable stimulation frequencies. In our experiments this phenomenon was visible in tetani evoked at two frequencies of stimulation: the lower immediately followed by the higher one. The force at the higher stimulation frequency was evidently depressed in relation to the force achieved during the control constant-frequency stimulations. This depression concerned the fast motor units and it was not observed in the slow units. The tetanic depression was initially found in the rat medial gastrocnemius muscle. However, it is not clear whether this phenomenon is specific only to the rat muscle or it concerns all mammals. Therefore, in the subsequent series of experiments, the tetanic depression was investigated in the motor units of the feline medial gastrocnemius, and the effect was also observed in all fast units. The maximum evoked depression exceeded 50% of the control values. Moreover, the analysis of the relationship between the amplitude of the tetanic depression and the degree of the tetanic fusion revealed that the strongest amplitude of depression was observed in the middle-fused tetani (with the fusion index in the range 0.5-0.7). The third experimental series proved that the tetanic depression could be visible in tetani evoked at a progressively increasing frequency of stimulation. Moreover, it was found that the effect of the force decrease could result from the prolongation of only one, the first interpulse interval. The amplitude of this decrease exceeded 20% of the control values. Summarizing, the tetanic depression is a phenomenon influencing the force of unfused tetani of the fast motor units at an increasing stimulation frequency. The depressive effect is present in various species of mammals, probably, including human. The amplitude of the depression depends on the fusion of the tetanic contraction. The physiological significance of tetanic depression is closely related to reduction of the importance of the motoneuronal firing rate.
2
Variability and plasticity of motor unit contractile properties
100%
Celichowski J.
Acta Neurobiologiae Experimentalis
|
2009
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tom 69
|
nr 3
EN
The motor unit contractile properties respond to changes in activity and in motor innervation of muscles. The contractions of isolated motor units evoked by the electrical stimulation of very thin fi laments of the ventral root were studied in anesthetized animals. Changes in the distribution of the three basic physiological types of motor units (fast fatigable, fast resistant and slow) in the rat medial gastrocnemius muscle and plasticity of their contractile properties as: contraction and relaxation time, force and fatigability were studied in ageing process, as effects of total and partial spinal cord injury, locomotor and vibration training. Moreover, distribution and variability of motor unit properties as well as innervation of skeletal muscles in male and female muscles were investigated. The comparison of motor unit properties in rat and cat muscle revealed considerable differences in twitch time and force parameters, distribution of motor unit types in muscles of the two species whereas the fatigability, ability to potentiate the force, sag and tetanic phenomenon revealed numerous similarities.
3
The influence of pattern of stimuli on changes in tension of unfused tetani of motor units in rat's medial gastrocnemius muscle
100%
Celichowski J.
Acta Neurobiologiae Experimentalis
|
1995
|
tom 55
|
nr 5
4
Tetanic depression: a phenomenon influencing the production of tension in fast-twitch motor units in rat medial gastrocnemius
100%
Celichowski J.
Acta Neurobiologiae Experimentalis
|
2001
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tom 61
|
nr 2
5
Content available Mechanisms underlying the regulation of motor unit contraction in the skeletal muscle
100%
Celichowski J.
|
|
nr 1
6
Motor units of medial gastrocnemius muscle in the rat during the fatigue test. I. Time course of unfused tetanus
100%
Celichowski J.
Acta Neurobiologiae Experimentalis
|
1992
|
tom 52
|
nr 1
7
Motor units of medial gastrocnemius muscle in the rat during the fatigue test. II. Changes in the time course of sequential tetani of fatigue test
100%
Celichowski J.
Acta Neurobiologiae Experimentalis
|
1992
|
tom 52
|
nr 2
8
The comparison of motor units contractile properties in medial gastrocnemius muscles of the normal and ADHD rats
63%
Ciechanowicz-Kowalczyk L. , Celichowski J.
Acta Neurobiologiae Experimentalis
|
2013
|
tom 73
|
nr Suppl.1
EN
The motor unit (MU) contractile properties in medial gastrocnemius muscle of young Wistar Kyoto rats, the model of attention deficit hyperactivity disorder (ADHD), and normal Wistar rats were studied. Functional isolation of motor units was achieved by electrical stimulation of single axons from ventral roots of L4–L5 spinal nerves. The motor units parameters: the force of twitch and tetanus, the contraction and the half-relaxation times and the properties of action potentials were analyzed for 47 and 60 MUs in ADHD and normal rats, respectively. The three types of MUs (FF, FR and S) in both groups were found. The distribution of FF, FR and S MUs for normal rats was: 26.7, 55.0 and 18.3% whereas the distribution of FF, FR and S MUs for ADHD rats was: 27.6, 44.7 and 27.6%. There were no statistical differences in motor units force and twitch time parameters. However, the twitch-to-tetanus ratio was higher for MUs in ADHD animals. Moreover, differences between shapes of twitch recordings were found and a ratio of the contraction to the half-relaxation times was lower for MUs in ADHD animals. The mean number of turns of MU action potentials was lower in all types of MUs of ADHD rats.
9
Division of motor units in Medial gastrocnemius muscle of the rat in the light of variability of their principal properties
63%
Grottel K. , Celichowski J.
Acta Neurobiologiae Experimentalis
|
1990
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tom 50
|
nr 6
10
Changes in contractile properties and action potentials of motor units in the rat medial gastrocnemius muscle during maturation
63%
Dobrzynska Z. , Celichowski J.
Acta Neurobiologiae Experimentalis
|
2013
|
tom 73
|
nr Suppl.1
EN
The development of motor unit (MU) properties after the elimination of polyneuronal innervation of muscle fibers has not been studied so far in contrast to the embryonic and neonatal development which are well known. Three groups of Wistar rats were investigated – 1 month old, 2 months old and the adult – 9 months old (1 m.o., 2 m.o. and 9 m.o. rats, respectively). The basic contractile properties and action potentials of MUs in the medial gastrocnemius muscle were analysed. In 1 mo rats the three main physiological types of MUs were already separated. It was visible that various MU’s contractile properties reached adult values at different stage of development. The twitch time parameters were similar for all studied age groups whereas the force was increasing, especially in the second month of life. The fatigue index for FF MUs as well as the twitch-to tetanus ratio for all three types of MUs in 1 and 2 m.o. rats were higher than for 9 m.o. rats. The amplitude and time parameters of MUAPs, except their latency, were not changing during the studied period of development.
11
Conrtactile propertiens and distribution of types of motor units innervated by axons from L.5 ventral roots in the rat medial gastrocnemius
63%
Taborowska M. , Celichowski J.
Acta Neurobiologiae Experimentalis
|
2009
|
tom 69
|
nr 3
EN
There is a limited data concerning the rostro-caudal distribution of motoneurons within the motor nucleus. In present experiments single motor units in rat medial gastrocnemius were studied and their contractile properties as well as percentage participation of different types of motor units belonging to subpopulations innervated by axons in L4 and L5 ventral roots were analyzed. Experiments were based on functional isolation and electrical stimulation of as many as possible axons from L4 and L5 ventral roots. 35 motor units innervated by L4 and 90 units innervated by L5 ventral root were studied. We found that the composition of the three physiological types of motor units (fast fatigable, fast resistant and slow) in the two subpopulations of motor units was similar. However, the twitch time parameters (the contraction time and half-relaxation time) were slightly longer in L4 in comparison with L5 subpopulation (the difference was signifi cant for fast resistant units) although the difference has not been refl ected in expected shift of a steep part of force-frequency of stimulation curve towards lower frequencies in L4 subpopulation of motor units. Force parameters were similar for motor units belonging to two subpopulations. The small differences between L4 and L5 subpopulations of motor units can be due to possible differences in a spatial distribution of their muscle fi bres in the semipennate medial gastrocnemius.
12
Content available remote Changes in contractile properties and action potentials of motor units in the rat medial gastrocnemius muscle during maturation
63%
Dobrzynska Z. , Celichowski J.
Journal of Physiology and Pharmacology
|
2016
|
tom 67
|
nr 1
13
Differences in the contractile properties and action potentials of motor units of the medical gastrocnemius muscle in young and adult male rats
63%
Dobrzynska Z. , Celichowski J.
Acta Neurobiologiae Experimentalis
|
2011
|
tom 71
|
nr S
EN
The growing up of organism is connected with considerable changes in neuromuscular and other systems. Numerous studies concerning a development of muscles and nerves have been carried out, especially within the embrional and neonatal life period although postnatal development of motor unit properties has not been studied. The aim of the present study was to document changes in contractile properties of skeletal muscles during a life period when embryonic and neonatal isoforms of myosin disappear but muscle mass is dynamically increasing. The two groups of animals, the young Wistar rats - 40 days old and the adult ones - 270 days old were investigated. The basic contractile properties and action potential of motor units (MUs) in the medial gastrocnemius muscle were analyzed. The body weight of young rats was three times lower than of adults (146.9 g vs 461.3 g), but the muscle mass was four times lower (0.313 g vs 1.246 g, respectively). The contraction time and half-relaxation time of fast MUs in 40-day-old rats were slightly longer than in adults. The twitch forces for the three MU types were two to three times lower in young rats, where the tetanus forces for all MU types were three to five times lower for 40-day-old animals. The twitch-to-tetanus ratio for all three types of MUs in young animals was significantly higher than in adult ones (0.43 vs 0.29 for FF, 0.31 vs 0.21 for FR, and 0.15 vs 0.08 for S MUs for young and adult rats, respectively). Moreover, considerable difference in the proportion of MU types was also observed. In adult rats higher participation of fast MUs was observed (33.7% of FF MUs and 55.4% of FR MUs) than in young ones (30.1% of FF and 41.1% of FR MUs) whereas slow MUs constituted 10.8% and 28.8% of studied populations of MUs in adult and young rats respectively. No significant differences in motor unit action potential parameters between young and adult animals were noticed.
14
Content available remote Variability and plasticity of motor unit properties in mammalian skeletal muscle
63%
Celichowski J. , Krutki P.
Biocybernetics and Biomedical Engineering
|
2012
|
tom Vol. 32, no. 4
33-45
EN
In the majority of mammalian skeletal muscles, contractile properties of motor units are variable and three main types of these units can be distinguished. The present review summarizes: results of studies of motor unit properties in the medial gastrocnemius muscle and their variability in two species, cats and rats, and studies on differences of motor unit properties in two genders. Moreover, plasticity of motor unit properties in rat medial gastrocnemius evoked by two kinds of spinal cord injury, total transection and hemisection, is reviewed, and effects of two types of training, treadmill locomotor and whole-body vibration training, are summarized. Finally, changes in the motor unit properties during the aging process are presented.
15
Differences between motor unit properties in distal and proximal muscles of rat hind limb
63%
Ciechanowicz I. , Celichowski J.
Acta Neurobiologiae Experimentalis
|
2007
|
tom 67
|
nr 3
16
The influence of endurance training on contractile properties of motor units in the rat medial gastrocnemius muscle
63%
Pogrzebna M. , Celichowski J.
Acta Neurobiologiae Experimentalis
|
2005
|
tom 65
|
nr 3
17
Tetanic depression of fast motor units during gradually increasing frequency of stimulation
63%
Lochynski D. , Celichowski J.
Acta Neurobiologiae Experimentalis
|
2007
|
tom 67
|
nr 3
18
Variability of contractile properties and action potentials of motor unit in flexor digitorum brevis nad medial gastrocnemiusmuscles in the rat
63%
Ciechanowicz-Kowalczyk I. , Celichowski J.
Acta Neurobiologiae Experimentalis
|
2009
|
tom 69
|
nr 3
EN
The differences between motor unit (MU) properties in foot (fl exor digitorum brevis, FDB) and sural (medial gastrocnemius, MG) muscles in anaesthetized Wistar rats were studied. In experiments functional isolation of single MUs was achieved by stimulation of thin fi laments from the L5–L6 and L4–L5 ventral roots for FDB and MG muscles, respectively. The mean muscle mass amounted to 76 mg for FDB and 895 mg for MG. The force and the motor unit action potential (MUAP) properties were analysed. The three types of MUs (FF, FR and S) in the MG muscle were found. Sag phenomenon was visible in all fast units at 40 Hz stimulation. In FDB, the slow MUs were not noted. Sag was visible for only a part of fast MUs at lower frequencies of stimulation. In the MG muscle the fatigue index had bimodal distribution, whereas in FDB the distribution was continuous. The twitch and maximum forces were approximately 8 times lower in FBD then in MG, whereas the contraction time was signifi cantly longer. The force-frequency curves of all motor units in FDB were shifted towards lower frequencies and comparison to the same type of MUs in MG. The MUAP durations for FF and FR MUs were longer whereas the MUAP amplitudes were higher for FF units in MG in relation to FDB. In conclusion, the variability of MU properties in distal and proximal muscle concerns all studied contractile parameters and likely refl ects different motor control strategy.
19
Changes in motor units properties in a rat model of amyothropic lateral sclerosis (ALS)
63%
Krisciak K. , Celichowski J.
Acta Neurobiologiae Experimentalis
|
2009
|
tom 69
|
nr 3
EN
ALS is a fatal neurodegenerative disorder characterized by developing muscle weakness and paralysis which is an effect of selective and progressive death of motoneurons. The experiments were carried out on motor units (MUs) of the medial gastrocnemius muscle in transgenic rats with hSOD1(G93A) mutation. The animals were divided into three groups: 3 months old, 4 months old and approximately 200 days old in nearly terminal state, when nerve stimulation revealed on average 6 MUs in the studied muscle. Because of considerable disturbances in contraction time (CT) and disappearance of sag effect, usually applied for MUs classifi cation as fast and slow, the division of MUs was based on 20 Hz tetanus index. Meanwhile, to distinguish fast fatigable (FF) from the fast resistant (FR) MUs the fatigue index (FatI) was applied. Results showed that MUs proportion changed radically in the course of the disease and in terminal state an increase of S and a decrease of fast MUs was observed. Moreover, CT increased gradually in all MU types. FatI of FF MUs increased but, at the same time, for FR and S gradually decreased. Twitch force as well as tetanus force in terminal group increased especially for FR and S MUs what indicates plastic changes in examined muscle (sprouting of surviving axons and collateral reinnervation), leading also to increased amplitude of MUs action potentials. EMG analysis additionally showed slowing of axonal conduction velocity or/and motor plate transduction.
20
Differences between małe and female motor unit properties of the medial gastocnemius muscle in rat
63%
Drzymala H. , Celichowski J.
Acta Neurobiologiae Experimentalis
|
2005
|
tom 65
|
nr 3
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