Biochemical and functional evidences for a GLUT-4 homologous protein in avian skeletal muscle.

The characteristics and modulation of glucose transport were investigated in skeletal muscles of 5-wk-old Muscovy ducklings (Cairina moschata). Glucose uptake by sarcolemmal vesicles isolated from gastrocnemius muscle followed typical Michaelis-Menten kinetics with a K(m) value (17 mM) similar to that described in equivalent mammalian preparations. Western blot analysis of duckling sarcolemma using antibodies directed against rat GLUT-4 transporter revealed an immunoreactive protein of similar molecular mass (45 kDa) to that present in rats.