Diffusional anisotropy is induced by subcellular barriers in skeletal muscle

Kinsey, Stephen T.; Locke, Bruce R.; Penke, Brigita; Moerland, Timothy S.

doi:10.1002/(sici)1099-1492(199902)12:1<1::aid-nbm539>3.3.co;2-m

Cited by 30 publications

(56 citation statements)

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“…6(A) represent the best fit of the experimental data to a diffusion model 39 that assumes a cylinder-shaped compartment, as inspired by the macroscopic and microscopic structural features of skeletal muscle, 41 42 The latter finding suggests that the diffusional anisotropy in rat muscle results from intracellular barriers well within the boundaries of the sarcolemma. Kinsey et al 43 have recently studied PCr diffusion anisotropy in isolated ex vivo goldfish muscle. Their data also provide convincing evidence that the radial restriction does not essentially involve the cell membrane.…”

Section: Dw-mrs and Cell Structure And Functionmentioning

confidence: 99%

“…Their data also provide convincing evidence that the radial restriction does not essentially involve the cell membrane. Kinsey et al 43 hypothesize that the sarcoplasmic reticulum and mitochondria are the principal intracellular structures that restrict diffusional transport of PCr in an orientation-dependent manner. Both have dimensions on the mm scale and have a structural organization that is compatible with the observed anisotropy.…”

Section: Dw-mrs and Cell Structure And Functionmentioning

confidence: 99%

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Diffusion NMR spectroscopy

Nicolay¹,

Braun²,

Graaf³

et al. 2001

NMR in Biomedicine

170

177

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MR offers unique tools for measuring molecular diffusion. This review focuses on the use of diffusionweighted MR spectroscopy (DW-MRS) to non-invasively quantitate the translational displacement of endogenous metabolites in intact mammalian tissues. Most of the metabolites that are observed by in vivo MRS are predominantly located in the intracellular compartment. DW-MRS is of fundamental interest because it enables one to probe the in situ status of the intracellular space from the diffusion characteristics of the metabolites, while at the same time providing information on the intrinsic diffusion properties of the metabolites themselves. Alternative techniques require the introduction of exogenous probe molecules, which involves invasive procedures, and are also unable to measure molecular diffusion in and throughout intact tissues. The length scale of the process(es) probed by MR is in the micrometer range which is of the same order as the dimensions of many intracellular entities. DW-MRS has been used to estimate the dimensions of the cellular elements that restrict intracellular metabolite diffusion in muscle and nerve tissue. In addition, it has been shown that DW-MRS can provide novel information on the cellular response to pathophysiological changes in relation to a range of disorders, including ischemia and excitotoxicity of the brain and cancer.

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Section: Dw-mrs and Cell Structure And Functionmentioning

confidence: 99%

Section: Dw-mrs and Cell Structure And Functionmentioning

confidence: 99%

Diffusion NMR spectroscopy

Nicolay¹,

Braun²,

Graaf³

et al. 2001

NMR in Biomedicine

170

177

View full text Add to dashboard Cite

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“…between the actin/ myosin chains, [35][36][37] in the sarcoplasmatic reticulum, or the mitochondria. 38 Secondly, they might be temporarily bound to macromolecules which themselves are strictly ordered within the muscle cells. This binding may be an unspecific attachment of polar or charged parts of the molecules or a specific affinity to enzymes during chemical reactions.…”

Section: Dipolar Effects Of Creatine Taurine and Lactatementioning

confidence: 99%

“…Diffusion-weighted 31 P-MR spectroscopy in skeletal muscle has shown restricted diffusion of phosphocreatine. [35][36][37][38]70,71 The self-diffusion of PCr is slower compared to water and it levels off when the displacement approaches the dimensions of the restricting compartment. 35,37,38,70,71 Since the diffusion-weighting gradients have been applied parallel and perpendicular to the muscle main fiber axis, this is an indication for the restricted motion of PCr within the elongated fibers 35,36 or subcellular structures such as mitochondria and sarcoplasmatic reticulum.…”

Section: Diffusion-weighted Spectroscopymentioning

confidence: 99%

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Dipolar coupling and ordering effects observed in magnetic resonance spectra of skeletal muscle

Boesch

Kreis

2001

NMR in Biomedicine

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Skeletal muscle is a biological structure with a high degree of organization at different spatial levels. This order influences magnetic resonance (MR) in vivo-in particular 1 H-spectra-by a series of effects that have very distinct physical sources and biomedical applications: (a) bulk fat (extramyocellular lipids, EMCL) along fasciae forms macroscopic plates, changing the susceptibility within these structures compared to the spherical droplets that contain intra-myocellular lipids (IMCL); this effect leads to a separation of the signals from EMCL and IMCL; (b) dipolar coupling effects due to anisotropic motional averaging have been shown for 1 H-resonances of creatine, taurine, and lactate; (c) aromatic protons of carnosine show orientation-dependent effects that can be explained by dipolar coupling, chemical shift anisotropy or by relaxation anisotropy; (d) limited rotational freedom and/or compartmentation may explain differences of 1 H-MR-visibility of the creatine/phosphocreatine resonances; (e) lactate 1 H-MR resonances are reported to reveal information on tissue compartmentation; (f) transverse relaxation of water and metabolites show multiple components, indicative of intra-, extracellular and/or macromolecular-bound pools, and in addition dipolar or J-coupling lead to a modulation of the signal decay, hindering straightforward interpretation; (g) diffusion weighted 31 P-MRS has shown restricted diffusion of phosphocreatine; (h) magnetization transfer (MT) indicates that there is a motionally restricted proton pool in spin-exchange with free creatine; reduced availability or restricted motion of creatine is particularly important for an estimation of ADP from 31 P-MR spectra, and in addition MT effects may alter the signal intensity of creatine 1 H-resonances following water-suppression pulses; (i) transcytolemmal water-exchange can be studied in 1 H-MRS by contrast-agents applied to the extracellular space; (k) transport of glucose across the cell membrane has been studied in diabetes patients using a combination of 13 C-and 31 P-MRS; and (l) residual quadrupolar interaction in 23 Na MR spectra from human skeletal muscle suggest that sodium ions are bound to ordered muscular structures.

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Dependence on diffusion time of apparent diffusion tensor of ex vivo calf tongue and heart

Kim

Chi-Fishman

Barnett

et al. 2005

Magnetic Resonance in Med

145

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The time dependence of the apparent diffusion tensor of ex vivo calf heart and tongue was measured for diffusion times ( d ) between 32 and 810 ms. The results showed evidence of restricted diffusion in the muscle tissues of both organs. In regions where the myofibers are parallel, the largest eigenvalue ( 1 ) of the diffusion tensor remained the same for all diffusion times measured, while the other eigenvalues ( 2 , 3 The anisotropy and reduction of intracellular water diffusion in skeletal muscle compared to free water diffusion based on diffusion-weighted nuclear magnetic resonance measurements was first reported by Cleveland et al. (1) in 1976. Since then, diffusion-weighted nuclear magnetic resonance spectroscopy (DW-MRS) has been used to study diffusion anisotropy induced by subcellular or cellular structures in muscles (2,3). The more powerful technique of diffusion tensor imaging (DTI) (4) also has been used to study the myoarchitecture of skeletal muscle (4 -7) as well as more complex muscular organs such as the heart (9 -12) and the tongue (13-15).van Donkelaar et al. (5) used DTI to generate a finite element mesh model to study skeletal muscle function. Sinha and Yao (6) used DTI with a tetrahedral encoding scheme to measure the anisotropy of water diffusion in in vivo human calf muscle and to map the elevation and azimuth angles of muscle fibers. Damon et al. (7) used DTI to measure the pennation angle in the skeletal muscle of rat and found the DTI-derived values to be highly correlated (r ϭ 0.89) with measurement by direct anatomic inspection. In the future, it may become possible to use DTI to monitor the progression of musculoskeletal diseases or the effect of exercise.Quantitative validation of DTI-based fiber orientation measurement has also been performed for the myocardium (8). Although cardiac muscle fiber is less striated than skeletal muscle fiber, DTI and histologic measurement of fiber orientation by Holmes et al. (8) Although DTI has been used to visualize the complex myoarchitecture of the tongue (13-15), only qualitative validation has been attempted to show the accuracy of DTI for the estimation of fiber orientation. A unique feature of lingual myoarchitecture is the heavily interwoven laminar structure of the muscle fibers in the intrinsic core region. Wedeen et al. (14) found the diffusion tensor in this region to be oblate with the eigenvector corresponding to the smallest eigenvalue oriented perpendicular to the plane containing the fibers. However, the capability of DTI to map the complex lingual myoarchitecture in detail and its usefulness for studying the effect of lingual pathology on swallowing and speech have not been demonstrated to date.In previous DTI studies of muscular organs, the diffusion time (time delay between the two diffusion sensitizing gradient pulses, d ) was kept constant, and the possible dependence of water diffusivity on diffusion time was not investigated. In the experiments described above, d for heart and skeletal muscle measurements was 20 to 35 m...

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Diffusional anisotropy is induced by subcellular barriers in skeletal muscle

Cited by 30 publications

References 0 publications

Diffusion NMR spectroscopy

Diffusion NMR spectroscopy

Dipolar coupling and ordering effects observed in magnetic resonance spectra of skeletal muscle

Dependence on diffusion time of apparent diffusion tensor of ex vivo calf tongue and heart

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