Insulin binding on cultured chick muscle cells: decrease in binding associated with cell fusion.
Binding of 125I-bovine and chicken insulin to cultured embryonic chick skeletal muscle cells was studied. Bovine and chicken insulin bound cultured cells with high affinities of 2.4 X 10(9)M-1 and 4.8 X 10(9)M-1 and low affinities of 2.4 X 10(7)M-1 and 3.7 X 10(7)M-1, respectively. Maximum insulin binding was achieved after 90 min of incubation at 20 degrees C and the maximum value was maintained for an additional 3 hr. Insulin binding increased in a linear manner with increasing nuclei number over a 5-fold range. Maximum insulin binding per nuclei decreased as cell fusion increased between 24 and 72 hr in culture, primarily due to a decrease in the number of low affinity insulin receptors.
D000818:Animals; D002417:Cattle; D002452:Cell Count; D002459:Cell Fusion; D002478:Cells, Cultured; D002642:Chick Embryo; D007328:Insulin / Q000378:metabolism*; D007700:Kinetics; D009132:Muscles / Q000166:cytology* / Q000378:metabolism; D010042:Ouabain / Q000378:metabolism; D013696:Temperature; D013997:Time Factors
D007328:Insulin; D010042:Ouabain