Effect of cytokines on cytosolic-free calcium in human platelets from essential hypertensives.
The different effects of cytokines on cytosolic-free calcium concentration ([Ca2+]i) and intracellular stored calcium were investigated in platelets from 35 essential hypertensive patients (HT) and 45 age- and sex-matched normotensive control subjects (NT). Erythropoietin (EPO) and interleukin 2 significantly increased platelet [Ca2+]i, whereas platelet-derived growth factor, and fibroblast growth factor had no significant effect on [Ca2+]i. The EPO-induced rise of [Ca2+]i was significantly higher in HT compared to NT (15.2 +/- 4.3 nmol/L v 1.3 +/- 1.7 nmol/L, P < .01). Preincubation with EPO significantly increased calcium in intracellular stores in platelets from HT and NT. Inhibition of protein kinase C significantly enhanced EPO-induced rise of stored calcium. It is concluded that an increased response of HT to EPO may be associated with essential hypertension.
Tepel
M
M
Medizinische Universitäts-Poliklinik, University of Münster, Germany.
Wischniowski
H
H
Neusser
M
M
Spieker
C
C
Zidek
W
W
D000328:Adult; D001792:Blood Platelets / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism*; D002118:Calcium / Q000097:blood*; D016207:Cytokines / Q000494:pharmacology*; D003600:Cytosol / Q000378:metabolism; D005260:Female; D006801:Humans; D006973:Hypertension / Q000097:blood*; D008297:Male; D008875:Middle Aged; D011493:Protein Kinase C / Q000037:antagonists & inhibitors / Q000378:metabolism; D013050:Spectrometry, Fluorescence
D016207:Cytokines; D011493:Protein Kinase C; D002118:Calcium