Ca2+ release in permeabilized human neutrophils induced by ciclosporin.
In suspensions of permeabilized human neutrophils, the free Ca2+ concentration was measured to test the effects of ciclosporin. Free Ca2+ concentration was measured with a Ca2(+)-selective electrode. Ciclosporin (500 ng/ml) induced a transient increase in free Ca2+ concentration (maximum delta pCa, 0.41 +/- 0.17). Thereafter, the free Ca2+ concentration decreased again, but did not reach the baseline level in most experiments. Ruthenium red, but not orthovanadate, abolished the slow decline of free Ca2+ concentration after the initial increase. The experiments suggest that ciclosporin may induce a release of Ca2+ from cellular organelles, e.g. the endoplasmic reticulum, and a partial reuptake in mitochondria. A release of cellular Ca2+ may play a role in ciclosporin-induced hypertension.
Zidek
W
W
Medizinische Universitäts-Poliklinik, Münster, FRG.
Neumann
K H
KH
D002118:Calcium / Q000378:metabolism*; D002463:Cell Membrane Permeability; D003524:Cyclosporins / Q000009:adverse effects / Q000494:pharmacology*; D006801:Humans; D006973:Hypertension / Q000139:chemically induced; D007424:Intracellular Fluid / Q000378:metabolism; D009504:Neutrophils / Q000187:drug effects* / Q000378:metabolism; D015388:Organelles / Q000187:drug effects; D012430:Ruthenium Red / Q000494:pharmacology; D014638:Vanadates / Q000494:pharmacology
D003524:Cyclosporins; D012430:Ruthenium Red; D014638:Vanadates; D002118:Calcium