REVIEW Phenformin binds to the AMP-activated protein kinase (AMPK). AMPK is an ultra-sensitive cellular energy sensor that monitors energy consumption and down-regulates ATP-consuming processes when activated. The biguanide phenformin has been shown to independently decrease ion transport processes, influence cellular metabolism and activate AMPK. Phenformin's hypoglycemic activity is related the effect it has in activating AMPK and fooling insulin sensitive cells into thinking that insulin levels are low and causing the body to use glucose as if in a state of low caloric consumption. This drug also seems to inhibit several varients of ATP-sensitive potassium channels (namely the receptor subtype Kir6.1).
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