| Abstract: | Effect of insulin on glucagon binding to rat epididymal adipocytes was studied in vitro. 125I]iodoglucagon binding to isolated adipocytes was increased by preincubation of the cells with insulin. Maximal increase was observed with 7 X 10(-10) M insulin. In Scatchard analysis, 125I]iodoglucagon competition data generated one binding site with a single affinity for glucagon binding in the cells pretreated with buffer alone. Pretreatment of the cells with insulin increased the affinity without changes in the number of binding sites. 125I]iodoglucagon binding to isolated adipocytes was not affected by pretreatment of the cells with luteinizing hormone, follicle-stimulating hormone, growth hormone, or with prolactin. These results suggest that insulin stimulates glucagon binding to adipocytes. |
