Elevated levels of parathyroid hormone in essential hypertensive patients with increased erythrocyte potassium efflux.
Previous observations suggest that Ca(2+)-dependent K+ efflux is increased in erythrocytes from spontaneously hypertensive rats. On the other hand, it has been reported that hyperparathyroidism induces an increase in Ca(2+)-dependent K+ efflux of human erythrocytes. To investigate whether Ca(2+)-dependent K+ efflux is altered in essential hypertension quinine-sensitive K+ efflux was measured in erythrocytes from 20 normotensive controls and 30 nontreated essential hypertensives. The quinine-sensitive K+ efflux was similar for hypertensive patients (593 +/- 20 mmol/L cells/h) as compared with normotensive controls (532 +/- 34 mmol/L cells/h). Ten hypertensives exhibited values of quinine-sensitive K+ efflux above an upper normal limit of 650 mmol/L cells/h. As compared with controls those patients presented elevated plasma levels of parathyroid hormone (P less than .05). In addition, a positive correlation was found between parathyroid hormone and quinine-sensitive K+ efflux in the above ten hypertensives (R = 0.85, P less than .001). These results suggest that an excess of parathyroid hormone may be involved in the increase of Ca(2+)-dependent K+ efflux present in some essential hypertensive patients.
Department of Medicine, University of Zaragoza, Spain.
J
J
Diez
E
E
Huarte
N
N
Esparza
D000328:Adult; D000368:Aged; D002118:Calcium / Q000502:physiology; D002463:Cell Membrane Permeability / Q000187:drug effects / Q000502:physiology; D004910:Erythrocyte Membrane / Q000187:drug effects / Q000502:physiology; D004912:Erythrocytes / Q000378:metabolism* / Q000502:physiology / Q000648:ultrastructure; D005260:Female; D006801:Humans; D006973:Hypertension / Q000097:blood* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D010281:Parathyroid Hormone / Q000097:blood*; D011188:Potassium / Q000097:blood*; D011803:Quinine / Q000494:pharmacology
D010281:Parathyroid Hormone; D011803:Quinine; D011188:Potassium; D002118:Calcium