Summary
The effects of insulin on amino acid transport were studied in freshly prepared suspensions of isolated hepatocytes from adult rats. Insulin stimulated the active transport of α-aminoisobutyric acid by increasing the influx. The onset of the insulin effect was delayed by thirty to sixty min. Insulin increased the Vmax of transport by about 60% without affecting the Km. Cycloheximide and actinomycin D inhibited hormonal action by 60 to 80%. Only the “A” system of transport was affected by insulin. Half-maximal stimulation of transport was observed with insulin at 2 to 3nmol/l, a concentration which also occupies about 50% of insulin-specific binding sites at steady state. Insulin did not antagonize the stimulatory effect of glucagon on amino acid transport.
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Le Cam, A., Freychet, P. Effect of insulin on amino acid transport in isolated rat hepatocytes. Diabetologia 15, 117–123 (1978). https://doi.org/10.1007/BF00422256
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DOI: https://doi.org/10.1007/BF00422256