Inhibitory effect of epinephrine on renal potassium secretion: a micropuncture study

Abstract

The effect of epinephrine on renal potassium excretion was examined in the rat. In group I KCl was infused acutely to increase plasma K (PK) by 2.0 meq/liter; urinary K excretion (UKV) rose by 1.22 mueq/min. In group II rats, which received a similar dose of KCl but with epinephrine, the increase in PK (delta = 0.8 meq/liter, P less than 0.001) was blunted and UKV was reduced (delta = 0.23 mueq/min, P less than 0.001). To determine whether the reduction in UKV resulted from the smaller increase in PK or from a direct action of epinephrine on renal K transport, a third group of animals received a lower dose of KCl. Despite similar PK levels, the epinephrine group excreted significantly less K in the urine (0.61 vs. 0.93 mueq/min). In group IV propranolol was infused with KCl; UKV was modestly increased. The effects of epinephrine on UKV were unrelated to changes in glomerular filtration rate, urine flow, or UNaV. Micropuncture results showed that at comparable PK levels epinephrine had no direct effect on K secretion by the distal tubule but indirectly inhibited K secretion in this nephron segment by reducing PK. In addition, epinephrine reduced K addition at tubular sites beyond the late distal tubule, most likely in the collecting tubule.

Electrolyte Disturbances in Patients With Chronic, Stable Asthma

“…11 Hypokalemia may also occur due to active inhibition of potassium secretion in the cortical collecting tubule, possibly caused by stimulation of membrane sodium potassium-dependent adenosine triphosphatase that results in hyperpolarization of the cellular membrane potential. 36 For chronic asthma, there was no previous study to evaluate the prevalence of hypokalemia in patients with chronic asthma receiving inhaled steroids and ␤ 2 -agonists. Although hypokalemia was only found in small number of our asthmatic patients (5.4%), the therapeutic drugs administered for the management of chronic asthma were found to have no effect on the serum potassium level.…”

Potassium homeostasis and its disturbances in children

“…Vasopressin has a stimulatory effect on renal potassium secretion, mediated by an initial increase in apical sodium permeability that leads to membrane depolarization and increased potassium secretion [38]. Insulin and epinephrine inhibit renal potassium secretion [40,41]. Insulin and epinephrine inhibit renal potassium secretion [40,41].…”

The Effect of Nebulized Salbutamol on Serum Potassium and Blood Sugar Level of Asthmatic Patients

“…Earlier studies also found decreased serum potassium levels to be the earliest form of electrolyte disturbance in asthma, and it was related to the use of β2-agonists. 7 Mildly decreased serum potassium levels have also been reported in untreated patients with severe asthma due to the stress of the asthmatic attacks.…”