title: Copper modifies the activity of sodium-transporting systems in erythrocyte membrane in patients with essential hypertension.
abstract: The aim of the study was to verify the hypothesis if copper could influence the activity of sodium-transporting systems in erythrocyte membrane that could be related to essential hypertension. The examined group of patients consisted of 15 men with hypertension. The control group was 11 healthy male volunteers. The Na+/H+ exchanger (NHE) activity in erythrocytes was determined according to Orlov et al. The activity of transporting systems (ATP-Na+/K+; co-Na+/K+/Cl-; ex-Na+/Li+; free Na+ and K+ outflow [Na+, K+-outflow]) was determined according to Garay's method. The concentration of copper in plasma was assessed using atomic absorption spectrometry. The activity of ATP-Na+/K+ (micromol/L red blood cells [RBCs]/h) in hypertensive patients was 2231.5 +/- 657.6 vs 1750.5 +/- 291 in the control (p < 0.05), the activity of co-Na+/K+/Cl- (micromol/L RBCs/h) in hypertensives was 171.3 +/- 77.9 vs 150.7 +/- 53.9 in the control (NS). Na+-outflow (micromol/L RBCs/h) in hypertensives was 118.3 +/- 51.6 vs 113.3 +/- 24.4 in the control (NS). The K+-outflow (micromol/L RBCs/h) in hypertensives was 1361.7 +/- 545.4 vs 1035.6 +/- 188.3 in the control (NS). The activity of ex-Na+/Li+ (micromol/L RBCs/h) in hypertensive patients was 266.1 +/- 76.1 vs 204.1 +/- 71.6 in the control (p < 0.05). NHE activity (mmol/L RBCs/h) in hypertensives was 9.7 +/- 2.96 vs 7.7 +/- 1.33 in the control (p < 0.05). In hypertensive patients, negative correlation was found between the activity of Na+/K+/Cl- co-transport and plasma copper concentration (Rs = -0.579, p < 0.05) and between the activity of ex-Na+/Li+ and plasma copper concentration (Rs = -0.508, p < 0.05). Plasma copper concentration significantly influences the activity of sodium transporting systems in erythrocyte membrane. Copper supplementation could be expected to provide therapeutic benefits for hypertensive patients.
authors.affiliation: Department of Nephrology, Transplantology and Internal Medicine, Pomeranian Medical University, Szczecin, Poland.
authors.forename: Karolina
authors.initials: K
authors.lastname: Kedzierska
authors.forename: Joanna
authors.initials: J
authors.lastname: Bober
authors.forename: Kazimierz
authors.initials: K
authors.lastname: Ciechanowski
authors.forename: Edyta
authors.initials: E
authors.lastname: Gołembiewska
authors.forename: Ewa
authors.initials: E
authors.lastname: Kwiatkowska
authors.forename: Iwona
authors.initials: I
authors.lastname: Noceń
authors.forename: Barbara
authors.initials: B
authors.lastname: Dołegowska
authors.forename: Grazyna
authors.initials: G
authors.lastname: Dutkiewicz
authors.forename: Dariusz
authors.initials: D
authors.lastname: Chlubek
mesh_terms: D002712:Chlorides / Q000097:blood; D003300:Copper / Q000097:blood* / Q000502:physiology; D004910:Erythrocyte Membrane / Q000187:drug effects / Q000378:metabolism*; D006801:Humans; D006973:Hypertension / Q000097:blood*; D008094:Lithium / Q000097:blood; D008297:Male; D011188:Potassium / Q000097:blood; D012044:Regression Analysis; D012964:Sodium / Q000097:blood*; D017923:Sodium-Hydrogen Exchangers / Q000097:blood* / Q000187:drug effects; D000254:Sodium-Potassium-Exchanging ATPase / Q000097:blood / Q000187:drug effects; D013054:Spectrophotometry, Atomic / Q000379:methods
chemical_list: D002712:Chlorides; D017923:Sodium-Hydrogen Exchangers; D003300:Copper; D008094:Lithium; D012964:Sodium; D000254:Sodium-Potassium-Exchanging ATPase; D011188:Potassium