Changes in Expression and Cellular Localization of Rat Skeletal Muscle ClC-1 Chloride Channel in Relation to Age, Myofiber Phenotype and PKC Modulation

The cellular localization of the alpha 2-subunit of the Na(+)-K(+)-ATPase was defined by immunoelectron microscopy, and the effect of insulin on the amount of alpha 2-immunoreactive subunits on the cell surface was quantitated. Two protocols were used for tissue fixation and immunolocalization. Protocol 1 was characterized by fixation with 2% paraformaldehyde, use of a monoclonal antibody, and detection with 3-nm-diameter gold-labeled Fab fragments or 10-nm gold-labeled immunoglobulin G. Protocol 2 was characterized by fixation with 4% paraformaldehyde plus 0.1% glutaraldehyde, use of a polyclonal antibody, and detection with 10-nm gold-labeled protein A. In control muscle, the alpha 2-subunit of the Na(+)-K(+)-ATPase was present at the plasma membrane and in intracellular tubular and vesicular structures located in subsarcolemmal and triadic regions. Acute insulin stimulation increased the number of immunolabeled alpha 2-subunits in the plasma membrane after both fixation protocols. The gain in the plasma membrane ranged from 1.5- to 3.7-fold and was significant at the level of P < 0.005. These results provide morphological quantitative evidence that the alpha 2-subunit of the Na(+)-K(+)-ATPase is present both at the plasma membrane and intracellularly in mammalian skeletal muscle and that insulin acutely increases its abundance in the muscle surface.

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Growth hormone and insulin-like growth factor-I restore the chloride channel conductance of aged rat skeletal muscle

Pharmacological Research ◽

10.1016/1043-6618(95)87736-3 ◽

1995 ◽

Vol 31 ◽

pp. 369

Author(s):

A. De Luca ◽

S. Pierno ◽

A. Roselli ◽

D. Cocchi ◽

D. Conte Camerino

Keyword(s):

Skeletal Muscle ◽

Growth Hormone ◽

Growth Factor ◽

Chloride Channel ◽

Insulin Like Growth Factor ◽

Channel Conductance ◽

Rat Skeletal Muscle ◽

Aged Rat ◽

Factor I ◽

Growth Factor I

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Adjacent interval analysis distinguishes among gating mechanisms for the fast chloride channel from rat skeletal muscle.

The Journal of Physiology ◽

10.1113/jphysiol.1989.sp017549 ◽

1989 ◽

Vol 410 (1) ◽

pp. 561-585 ◽

Cited By ~ 23

Author(s):

A L Blatz ◽

K L Magleby

Keyword(s):

Skeletal Muscle ◽

Interval Analysis ◽

Chloride Channel ◽

Rat Skeletal Muscle ◽

Gating Mechanisms

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Stilbene derivatives inhibit the activity of the inner mitochondrial membrane chloride channels

Cellular & Molecular Biology Letters ◽

10.2478/s11658-007-0019-9 ◽

2007 ◽

Vol 12 (4) ◽

Cited By ~ 10

Author(s):

Izabela Koszela-Piotrowska ◽

Katarzyna Choma ◽

Piotr Bednarczyk ◽

Krzysztof Dołowy ◽

Adam Szewczyk ◽

...

Keyword(s):

Skeletal Muscle ◽

Chloride Channel ◽

Chloride Channels ◽

Mitochondrial Membrane ◽

Disulfonic Acid ◽

Mitochondrial Membranes ◽

Rat Skeletal Muscle ◽

Inner Mitochondrial Membrane ◽

Stilbene Derivatives ◽

Rat Heart Mitochondria

AbstractIon channels selective for chloride ions are present in all biological membranes, where they regulate the cell volume or membrane potential. Various chloride channels from mitochondrial membranes have been described in recent years. The aim of our study was to characterize the effect of stilbene derivatives on single-chloride channel activity in the inner mitochondrial membrane. The measurements were performed after the reconstitution into a planar lipid bilayer of the inner mitochondrial membranes from rat skeletal muscle (SMM), rat brain (BM) and heart (HM) mitochondria. After incorporation in a symmetric 450/450 mM KCl solution (cis/trans), the chloride channels were recorded with a mean conductance of 155 ± 5 pS (rat skeletal muscle) and 120 ± 16 pS (rat brain). The conductances of the chloride channels from the rat heart mitochondria in 250/50 mM KCl (cis/trans) gradient solutions were within the 70–130 pS range. The chloride channels were inhibited by these two stilbene derivatives: 4,4′-diisothiocyanostilbene-2,2′-disulfonic acid (DIDS) and 4-acetamido-4′-isothiocyanostilbene-2,2′-disulfonic acid (SITS). The skeletal muscle mitochondrial chloride channel was blocked after the addition of 1 mM DIDS or SITS, whereas the brain mitochondrial channel was blocked by 300 μM DIDS or SITS. The chloride channel from the rat heart mitochondria was inhibited by 50–100 μM DIDS. The inhibitory effect of DIDS was irreversible. Our results confirm the presence of chloride channels sensitive to stilbene derivatives in the inner mitochondrial membrane from rat skeletal muscle, brain and heart cells.

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Creatine transporter protein content, localization, and gene expression in rat skeletal muscle

AJP Cell Physiology ◽

10.1152/ajpcell.2001.280.3.c415 ◽

2001 ◽

Vol 280 (3) ◽

pp. C415-C422 ◽

Cited By ~ 35

Author(s):

R. Murphy ◽

G. McConell ◽

D. Cameron-Smith ◽

K. Watt ◽

L. Ackland ◽

...

Keyword(s):

Gene Expression ◽

Skeletal Muscle ◽

Protein Content ◽

Cross Sections ◽

Cellular Localization ◽

Immunohistochemical Analysis ◽

Rat Skeletal Muscle ◽

Creatine Transporter ◽

Transporter Protein ◽

Muscle Types

The present study examined the gene expression and cellular localization of the creatine transporter (CreaT) protein in rat skeletal muscle. Soleus (SOL) and red (RG) and white gastrocnemius (WG) muscles were analyzed for CreaT mRNA, CreaT protein, and total creatine (TCr) content. Cellular location of the CreaT protein was visualized with immunohistochemical analysis of muscle cross sections. TCr was higher ( P ≤ 0.05) in WG than in both RG and SOL, and was higher in RG than in SOL. Total CreaT protein content was greater ( P ≤ 0.05) in SOL and RG than in WG. Two bands (55 and 70 kDa) of the CreaT protein were found in all muscle types. Both the 55-kDa (CreaT-55) and the 70-kDa (CreaT-70) bands were present in greater ( P ≤ 0.05) amounts in SOL and RG than in WG. SOL and RG had a greater amount ( P ≤ 0.05) of CreaT-55 than CreaT-70. Immunohistochemical analysis revealed that the CreaT was mainly associated with the sarcolemmal membrane in all muscle types. CreaT mRNA expression per microgram of total RNA was similar across the three muscle types. These data indicate that rat SOL and RG have an enhanced potential to transport Cr compared with WG, despite a higher TCr in the latter.

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