Biochemical and biophysical research communications
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Biochem. Biophys. Res. Commun. · Jan 2006
Altered expression and function of sodium channels in large DRG neurons and myelinated A-fibers in early diabetic neuropathy in the rat.
Differential alterations of sodium channels in small nociceptive C-fiber DRG neurons have been implicated in diabetic neuropathy. In this study, we investigated sodium currents and the expression of sodium channels in large A-fiber DRG neurons in diabetic rats. Compared with controls, large neurons from diabetic rats showed significant increases in both total and TTX-S sodium currents and approximately -15mV shifts in their voltage-dependent activation kinetics. ⋯ Immunofluorescence studies showed significant increases in the levels and number of large DRG neurons from diabetic rats expressing Na(v)1.2, Na(v)1.3, Na(v)1.7, and Na(v)1.9 whereas Na(v)1.8 decreased. We also observed a decrease in the number of nodes of Ranvier expressing Na(v)1.8 and in staining intensity of Na(v)1.6 and Na(v)1.8 at nodes. Our results suggest that alterations of sodium channels occur in large DRG neurons and A-fibers, and may play an important role in diabetic sensory neuropathy.
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Biochem. Biophys. Res. Commun. · Jan 2006
High-fat diet feeding impairs both the expression and activity of AMPKa in rats' skeletal muscle.
To investigate the effects of high-fat feeding on the expression and activity of AMPK in rats' skeletal muscle. ⋯ High-fat feeding impaired both the expression and activities of AMPKa, while activating AMPKa by metformin obviously ameliorated high-fat induced insulin resistance, thus indicating a possible role of AMPKa in lipotoxicity.