Insulin Downregulates Alpha-2 Adrenergic Receptors in Cultured Glial Cells
Our previous studies have suggested that insulin can modulate central catecholaminergic systems. In the present study we have investigated this further by examining the actions of this peptide on the regulation of α2-adrenergic receptors in glial cells. Using [3H]-yohimbine as a ligand for α2-adrenergic receptors, we have demonstrated that insulin is able to decrease [3H]-yohimbine binding to glia in a time- and dose-dependent manner. Saturation experiments followed by Scatchard analyses revealed that this was due to a decreased number of α2-adrenergic receptors. These results suggest that insulin, by modulating α2adrenergic receptor levels, is able to regulate the amount of NE present in the synaptic cleft.
KeywordsGlial Cell Insulin Receptor Synaptic Cleft Scatchard Analysis Saturation Experiment
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