ISSN:
1432-0428
Keywords:
Key words GLUT 4, glucose transporter, insulin resistance, (fa/fa) rats, GLUT 1, Zucker rats, skeletal muscle, perineurial sheath, crude membranes, hyperglycaemia, metformin.
Source:
Springer Online Journal Archives 1860-2000
Topics:
Medicine
Notes:
Summary Recently, we demonstrated that approximately 60 % of GLUT 1 in a crude membrane fraction of rat skeletal muscle originates from perineurial sheaths. To study the in vivo regulation of GLUT 1 expression in different tissues in muscles, we measured the level of GLUT 1 in crude muscle membranes and in perineurial sheaths in diabetic (fa/fa) Zucker rats and lean controls, with and without metformin treatment. The GLUT 1 concentration in perineurial sheaths was identical in all four groups of rats, both when measured by quantitative immunofluorescence and by immunoblotting and densitometry. In a fraction of crude membranes of soleus muscles GLUT 1 expression was more than two-fold higher in (fa/fa) rats than in lean controls (p〈0.005). Metformin treatment significantly elevated GLUT 1 in control rats (p〈0.05) and tended to decrease GLUT 1 in diabetic rats (p〈0.075). The expressions of GLUT 1 and GLUT 4 in crude muscle membranes were inversely correlated (p〈0.01), and GLUT 1 expression correlated positively with fasting glucose (p〈0.05). In conclusion, GLUT 1 expression in perineurial sheaths is unaffected by alterations in glucose homeostasis and by the genes responsible for obesity and diabetes in the Zucker rat. GLUT 1 expression in a crude membrane fraction of soleus muscle is increased in the diabetic animals, likely due to an increased expression in muscle cells proper. [Diabetologia (1994) 37: 443–448]
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/s001250050130
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