NBME 22 Answers ↦
I know Insulin cause shift K+ into cells due to closing of ATP-sensitive K channels (blocking K from leaving)? Does it increase K in the cells by another mechanism?
@dentist - Insulin stimulates the Na+-K+-ATPase pump, this drives K+ into the cell (Source: Amboss)
Another mechansim = acidosis causes hyperkalemia due to H+/K+ antiporters. H+ is high in blood so shifts into cells via this antiporter, which shifts K+ out. --potassium section of acid/base chapter in Costanzo physiology
super high blood glucose; super high glucose spillage into urine; lots of peeing = volume depleted (“osmotic diuresis”)
because insulin normally stimulates Na/K ATPase, which sequesters K inside cell. lack of insulin means that there will be more K outside of the cell causing hyperkalemia. however, you are still total body K depleted due to osmotic diuresis. so the hyperkalemia is mainly due to a shift of K from the intracellular (where the vast majority of your K is inside your body is) to the extracellular space.
*where the vast majority of your K is inside your body