Acetazolamide-sensitive and resistant carbonic anhydrase activity in rat and rabbit skeletal muscles of different fiber type composition

The purpose of this study was to examine the distribution of myosin isozymes in rodent (Rattus norvegicus) hindlimb skeletal muscles and regions of muscle known to have contrasting fiber-type composition. Muscle samples were analyzed for Ca2+-regulated myofibril adenosine triphosphatase (ATPase) activity, Ca2+-activated myosin ATPase activity, myosin isozyme profile, and myosin light chain profile. Four isozymes of myosin were identified based on native protein and light chain electrophoresis patterns: one associated primarily with slow-twitch muscle (SM) and three associated primarily with fast-twitch muscle (FM). Multiple linear regression analysis of Ca2+-regulated myofibril ATPase activity (pCA 4) vs. measured isozyme profile was used to estimate the myofibril ATPase activities of the individual isozymes (FM1 = 0.86, FM2 = 0.52, FM3 = 0.31, and SM = 0.15 mumol Pi formed . mg myofibril protein-1 . min-1 at 25 degrees C, n = 180, P less than 0.001). Differences in the native isozyme profiles and myofibril ATPase activities between muscles and muscle regions of similar fiber type composition indicate that a given fiber type may not necessarily express a single isozyme profile. These data are consistent with the hypothesis that, among rodent hindlimb skeletal muscles and inherently their motor units, a range of myosin isozyme profiles exists that may provide a broad range of mechanical expression.

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Diversity in levels of intracellular total creatine and triglycerides in human skeletal muscles observed by1H-MRS

Journal of Applied Physiology ◽

10.1152/jappl.1999.87.6.2068 ◽

1999 ◽

Vol 87 (6) ◽

pp. 2068-2072 ◽

Cited By ~ 71

Author(s):

Jesús Rico-Sanz ◽

E. Louise Thomas ◽

Gabriele Jenkinson ◽

Šárka Mierisová ◽

Richard Iles ◽

...

Keyword(s):

Magnetic Resonance ◽

Magnetic Resonance Spectroscopy ◽

Tibialis Anterior ◽

Skeletal Muscles ◽

Fiber Type ◽

Resonance Spectroscopy ◽

Fiber Type Composition ◽

Type Composition ◽

Total Creatine ◽

Human Skeletal Muscles

We used1H-magnetic resonance spectroscopy to noninvasively determine total creatine (TCr), choline-containing compounds (Cho), and intracellular (IT) and extracellular (between-muscle fibers) triglycerides (ET) in three human skeletal muscles. Subjects' ( n = 15 men) TCr concentrations in soleus [Sol; 100.2 ± 8.3 (SE) mmol/kg dry wt] were lower ( P < 0.05) than those in gastrocnemius (Gast; 125.3 ± 9.2 mmol/kg dry wt) and tibialis anterior (TA; 123.7 ± 8.8 mmol/kg dry wt). The Cho levels in Sol (35.8 ± 3.6 mmol/kg dry wt) and Gast (28.5 ± 3.5 mmol/kg dry wt) were higher ( P < 0.001 and P < 0.01, respectively) compared with TA (13.6 ± 2.4 mmol/kg dry wt). The IT values were found to be 44.8 ± 4.6 and 36.5 ± 4.2 mmol/kg dry wt in Sol and Gast, respectively. The IT values of TA (24.5 ± 4.5 mmol/kg dry wt) were lower than those of Sol ( P < 0.01) and Gast ( P < 0.05). There were no differences in ET [116.0 ± 11.2 (Sol), 119.1 ± 18.5 (Gast), and 91.4 ± 19.2 mmol/kg dry wt (TA)]. It is proposed that the differences in metabolite levels may be due to the differences in fiber-type composition and deposition of metabolites due to the adaptation of different muscles during locomotion.

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MYOSIN LIGHT CHAIN PATTERNS OF SINGLE FIBERS AND FIBER TYPE COMPOSITION OF FAST AND SLOW SKELETAL MUSCLES IN RATS

Japanese Journal of Physical Fitness and Sports Medicine ◽

10.7600/jspfsm1949.35.248 ◽

1986 ◽

Vol 35 (5) ◽

pp. 248-254 ◽

Cited By ~ 1

Author(s):

TAKAO SUGIURA ◽

HIDEKI MATOBA ◽

SHUNSUKE MORITA ◽

NAOTOSHI MURAKAMI

Keyword(s):

Light Chain ◽

Skeletal Muscles ◽

Myosin Light Chain ◽

Fiber Type ◽

Single Fibers ◽

Fiber Type Composition ◽

Type Composition

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Regulation of carbonic anhydrase III by thyroid hormone: opposite modulation in slow- and fast-twitch skeletal muscle

Biochemistry and Cell Biology ◽

10.1139/o87-103 ◽

1987 ◽

Vol 65 (9) ◽

pp. 790-797 ◽

Cited By ~ 11

Author(s):

Pierre Frémont ◽

Claude Lazure ◽

Roland R. Tremblay ◽

Michel Chrétien ◽

Peter A. Rogers

Keyword(s):

Skeletal Muscle ◽

Thyroid Hormone ◽

Carbonic Anhydrase ◽

Soleus Muscle ◽

Fiber Type ◽

Type I ◽

Fiber Type Composition ◽

Carbonic Anhydrase Iii ◽

Type Composition ◽

Slow Twitch

This laboratory previously reported that a major 30 kilodalton (kDa) protein of the soluble cytoplasmic fraction of the rat slow-twitch soleus muscle is modulated by thyroid hormone. This protein has been purified and a portion of the primary structure has been determined. The sequence analysis suggested that the 30-kDa protein is carbonic anhydrase III (CA III; EC 4.2.1.1). The reaction of the protein with a CA III specific antibody and the similar modulation of CA III by thyroid hormone also support this conclusion. Immunochemical quantification of CA III and measurement of CA activity were performed in skeletal muscles of defined fiber-type composition from rats that were rendered hyperthyroid by treatment with 3,3′,5-triiodo-L-thyronine. These experiments revealed that CA activity and CA III content are deinduced in the soleus muscle (primarily type I fibers) and induced in the superficial vastus lateralis muscle (primarily type IIb), whereas no changes were detected in the tibialis anterior muscle (primary type IIa). These results show that the modulation of CA III by thyroid hormone in rat skeletal muscle is not limited to the slow-twitch soleus muscle and that the amplitude and direction of this modulation are directly related to the initial fiber-type composition of the skeletal muscle.

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