title: Sodium/lithium countertransport and intracellular calcium concentration in patients with essential hypertension and coronary heart disease.
abstract: The present study was designed to test the hypothesis that enhanced intracellular calcium signalling and increased sodium/lithium countertransport (Na(+)/Li(+) CT) activity may be associated with coronary heart disease (CHD) in non-diabetic patients with essential hypertension. Platelet-activating factor (PAF)-evoked rises in the intracellular calcium concentration ([Ca(2+)](i)) were measured in Epstein-Barr-virus-immortalized lymphoblasts from 62 hypertensive patients with CHD and 34 patients without CHD. Na(+)/Li(+) CT activity was assessed in erythrocytes from 80 hypertensive patients with CHD and 46 patients without CHD. Baseline values of unstimulated and PAF-stimulated [Ca(2+)](i) were not significantly different between hypertensive subjects with (baseline, 126+/-5 nmol/l; stimulated, 550+/-43 nmol/l) and without (baseline, 125+/-5 nmol/l; stimulated, 654+/-105 nmol/l) CHD. Similarly, Na(+)/Li(+) CT activity was not significantly different between the two groups (patients with CHD, 219+/-8 micromol x l(-1) x h(-1); patients without CHD, 234+/-10 micromol x l(-1) x h(-1)). We conclude that intracellular signal transduction, as indicated by PAF-induced rises in [Ca(2+)](i) and Na(+)/Li(+) CT activity, is not associated with an increased risk of CHD in non-diabetic patients with essential hypertension.
authors.affiliation: Department A of Internal Medicine, Ernst Moritz Arndt University Greifswald, Loefflerstrasse 23a, D-17487 Greifswald, Germany. gruska@uni-greifswald.de
authors.forename: Sybille
authors.initials: S
authors.lastname: Gruska
authors.forename: Ingo
authors.initials: I
authors.lastname: Jendral
authors.forename: Rainer
authors.initials: R
authors.lastname: Rettig
authors.forename: Günter
authors.initials: G
authors.lastname: Kraatz
mesh_terms: D000368:Aged; D017920:Antiporters / Q000097:blood*; D001402:B-Lymphocytes / Q000378:metabolism; D002118:Calcium / Q000097:blood*; D002472:Cell Transformation, Viral; D002478:Cells, Cultured; D003327:Coronary Disease / Q000097:blood* / Q000150:complications; D004912:Erythrocytes / Q000378:metabolism; D005260:Female; D006801:Humans; D006973:Hypertension / Q000097:blood* / Q000150:complications; D008297:Male; D008875:Middle Aged; D010972:Platelet Activating Factor / Q000494:pharmacology; D012044:Regression Analysis; D015398:Signal Transduction / Q000187:drug effects
chemical_list: D017920:Antiporters; D010972:Platelet Activating Factor; C045885:sodium-lithium countertransporter; D002118:Calcium