Insulin receptor regulation and desensitization in rat hepatoma cells: concomitant changes in receptor number and in binding affinity
M Crettaz, CR Kahn - Diabetes, 1984 - Am Diabetes Assoc
We have studied the effects of chronic exposure to insulin on the binding and the biologic
activity of the hormone using a well-differentiated cell line (Fao) derived from the Reuber
H35 rat hepatoma. Prolonged incubation (24 h) with 10− 6 M insulin produced a 20–25%
decrease in binding of tracer concentrations (2× 10− 11 M) of125I-insulin, and a leftward
shift of the curve for inhibition by unlabeled insulin. Scatchard analysis of the binding data
revealed that a 75–80% decrease in the number of binding sites had occurred in the insulin …
activity of the hormone using a well-differentiated cell line (Fao) derived from the Reuber
H35 rat hepatoma. Prolonged incubation (24 h) with 10− 6 M insulin produced a 20–25%
decrease in binding of tracer concentrations (2× 10− 11 M) of125I-insulin, and a leftward
shift of the curve for inhibition by unlabeled insulin. Scatchard analysis of the binding data
revealed that a 75–80% decrease in the number of binding sites had occurred in the insulin …
Insulin receptor regulation and desensitization in rat hepatoma cells. The loss of the oligomeric forms of the receptor correlates with the change in receptor affinity.
We have previously reported that prolonged incubations of Fao cells, a cell line derived from
the well-differentiated Reuber H35 rat hepatoma, with 10 (-6) M insulin, induced a decrease
in receptor number (down-regulation), an increase in receptor affinity for insulin, and a loss
of insulin's biological effect (desensitization). In the present study, we have investigated the
relationship between these changes in insulin binding and action and changes in the
structure of the insulin receptor. Intact cells were surface labeled with Na125I and …
the well-differentiated Reuber H35 rat hepatoma, with 10 (-6) M insulin, induced a decrease
in receptor number (down-regulation), an increase in receptor affinity for insulin, and a loss
of insulin's biological effect (desensitization). In the present study, we have investigated the
relationship between these changes in insulin binding and action and changes in the
structure of the insulin receptor. Intact cells were surface labeled with Na125I and …