title: Study of the interrelationship between dopaminergic activity and potassium ion.
abstract: The present study was designed to examine the interrelationship between dopaminergic neuron activity and potassium ion in the normotensive elderly subjects with a stable physical condition. Potassium chloride loaded intravenously (40mEq/day) in 5 subjects increased urinary excretions of Na (p less than 0.01) and dopamine. Furosemide administered orally (20mg/day) in 5 subjects increased urinary excretions of Na (p less than 0.05), dopamine (p less than 0.01) and K. Spironolactone administered orally (75mg/day) in 5 subjects brought an increase of urinary excretion of Na and a decrease of urinary excretions of K and dopamine, although these changes were not statistically significant. Metoclopramide, a dopamine antagonist, administered orally (15mg/day) in 5 subjects brought about a tendency of decrease in urinary excretions of Na and K. Between urinary amounts of K and dopamine, a positive correlation (gamma = 0.702, p less than 0.001, n = 22) was recognized. From these results, the change of the excretion of dopamine seemed to be parallel with that of K, and therefore it is suggested that a mechanism involved in the excretion of dopamine into the urine has a close relationship with that excreting K. The possible mechanisms are discussed.
mesh_terms: D000368:Aged; D004298:Dopamine / Q000652:urine*; D005665:Furosemide / Q000494:pharmacology; D006801:Humans; D008787:Metoclopramide / Q000494:pharmacology; D008875:Middle Aged; D011188:Potassium / Q000652:urine*; D011189:Potassium Chloride / Q000494:pharmacology; D012964:Sodium / Q000652:urine*; D013148:Spironolactone / Q000494:pharmacology
chemical_list: D013148:Spironolactone; D011189:Potassium Chloride; D005665:Furosemide; D012964:Sodium; D008787:Metoclopramide; D011188:Potassium; D004298:Dopamine