Distribution of Potassium acrossthe Cell MembraneTheNa+/K+ATPasemembranepumpandpermeabilityof ionchannels
Distribution of Potassium across the Cell Membrane The Na+ /K+ATPase membrane pump and permeability of ion channels
InfluencingFactors1.Hormones insulin, glucagoncatecholamines,thyroid hormoneNa/KATPast2.Serum [Kt][K+]↑Catecholamine3.pHofECFandplasmaInsulinosmolalityH+4.Othersrate of cell breakdownhypoxia, hypothermia, exercise
1.Hormones — insulin, glucagon, catecholamines, thyroid hormone 2.Serum [K+ ] 3.pH of ECF and plasma osmolality 4.Others — rate of cell breakdown, hypoxia, hypothermia, exercise Influencing Factors [K+]↑ Na+ Na+ /K+ - ATPase K+ K+ H+ Catecholamine Insulin
Regulation of Renal Potassium ExcretionH20H20NaNa+AldosteroneBownan'sCIcapsuleProximalNat/K+ATPasetubuleDistaltubuleH+-K+ATPaseNa+/K+ATPase(Mtactivated)Glomerulus精#oolectingCapillaryTubuleLooplofLnThenephronandcollectingtubule
Regulation of Renal Potassium Excretion Filtration, reabsorption and secretion of potassium The nephron and collecting tubule ClNa+ /K+ATPase( Mg2+ activated) Na+ /K+ATPase H+ - K+ ATPase
Regulation of Renal Potassium Excretion*Filtration,reabsorptionandsecretionofpotassiumSecretionofpotassiuminthedistalandcollectingtubulesprincipal cells, with Na+/K+ATPasemembranepump, for secretionof Kt
Regulation of Renal Potassium Excretion Filtration, reabsorption and secretion of potassium Secretion of potassium in the distal and collecting tubules principal cells, with Na+ /K+ATPase membrane pump, for secretion of K+
lumenbloodNatNatCICIK+Principal CellCO2COHHCO3CICIK+CellIntercalated
lumen Principal Cell blood K+ Na+ Na+ K+ ClClK+ CO2 HCO3 - ClClH + K + CO2 Intercalated Cell