Structural and Functional Rearrangement of Muscle Spindles in Rats under Conditions or Zero Gravity

Volodina, A. V.; Pozdnyakov, O. M.

doi:10.1023/b:bebm.0000024397.55532.3d

Cited by 4 publications

(4 citation statements)

References 2 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Against a backdrop of immobilization‐related effects in nonhibernating animals, hibernation seems to cause significantly less disuse atrophy. For example, muscle spindles degenerate with unloading or weightlessness including disordered myofibril orientation and ringed fibers (Takahashi & Kimura, ; B. Tang, Fan, & Wu, ; Volodina & Pozdnyakov, ).…”

Section: Discussionmentioning

confidence: 99%

“…For example, muscle spindles degenerate with unloading or weightlessness including disordered myofibril orientation and ringed fibers (Takahashi & Kimura, 1997;B. Tang, Fan, & Wu, 2004;Volodina & Pozdnyakov, 2004).…”

Section: Discussionmentioning

confidence: 99%

“…Mechanical unloading or space travel causes muscle atrophy and a decline in peak force and power, with slow‐twitch muscle fibers becoming much weaker than fast‐twitch ones (Diffee, Caiozzo, Herrick, & Baldwin, ; Gao, Arfat, Wang, & Goswami, ; Leterme & Falempin, ; Williams, Kuipers, Mukai, & Thirsk, ). Ultrastructural changes constitute an important parameter to judge the degree of muscle atrophy or damage (Diffee et al, ; Volodina & Pozdnyakov, ). These include loss of nuclei, myofibrils, and sarcotubules, such as in the anterior tibial and soleus (SOL) muscles of hindlimb immobilized rats (Appell, ; Boonyarom & Inui, ; Fitts, Riley, & Widrick, ; Kim, Kwon, & Kim, ).…”

Section: Introductionmentioning

confidence: 99%

“…Skeletal muscle ultrastructure is not only an important parameter for judging the degree of muscle injury or atrophy, it also sheds light upon anti-disuse atrophy mechanisms in hibernating animals. However, such studies appear to be extremely limited (Diffee et al, 1991;Volodina & Pozdnyakov, 2004). Effects of long-term hibernation inactivity on mammal skeletal muscle ultrastructure was only reported in bats (Myotis myotis) and focused on the structure of mitochondria and Z-lines, however, the information on intrafusal (muscle spindle) fibers was lacking (Klika & Zaitsova, 1984).…”

mentioning

confidence: 99%

See 3 more Smart Citations

Novel findings on ultrastructural protection of skeletal muscle fibers during hibernation of Daurian ground squirrels: Mitochondria, nuclei, cytoskeleton, glycogen

Wang

Jiang

Cao

et al. 2019

Journal Cellular Physiology

View full text Add to dashboard Cite

We examined ultrastructure protective phenomena and mechanisms of slow and fast muscles in hibernating Daurian ground squirrels (Spermophilus dauricus). Some degenerative changes such as slightly decreased sarcomere length and vacuolization occurred in hibernation, but periaxonal capsular borders in intrafusal fibers remained distinct and the arrangement of extrafusal fibers and Z‐lines unscathed. In soleus samples, the number of glycogenosomes more than tripled during hibernation. The expression of phosphorylated glycogen synthase remained unaltered while that of glycogen phosphorylase decreased during hibernation. The number of extensor digitorum longus glycogenosomes decreased and the expression of phosphorylated glycogen synthase decreased, while glycogen phosphorylase expression remained unaltered. The nuclei number remained unchanged. Kinesin and desmin, preventors of nuclear loss and damage, were maintained or just slightly reduced in hibernation. The single‐fiber mitochondrial concentration and sub‐sarcolemmal mitochondrial number increased in both muscle types. The expression of vimentin, which anchors mitochondria and maintains Z‐line integrity, was increased during and after hibernation. Also, dynamin‐related protein 1, mitochondrial fission factor, and adenosine triphosphate synthase were elevated in both muscle types. These findings confirm a remarkable ultrastructure preservation and show an unexpected increase in mitochondrial capacity in hibernating squirrels.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%