The effect of human defensins on the level of cytoplasmic Ca2+ in platelets
Tkachenko, S.B.; Kokriakov, V.N.; Ashmarin, I.P.; Grachev, S.V.; Kubatiev, A.A.
Biulleten' Eksperimental'noi Biologii i Meditsiny 118(12): 600-603
1994
ISSN/ISBN: 0365-9615 PMID: 7703453 Document Number: 437164
The effect of the total fraction of human defensins (HNP-1, HNP-2, HNP-3) on cytoplasmic calcium concentration was studied in platelets of healthy donors. Defensin concentrations of 0.1 microgram/ml did not affect the Ca-2+ level in platelets labeled with Fura-2AM when incubated during the period of time up to 10 minutes. However, higher defensin concentrations (100 microgram/ml) increased Ca-2+ concentration in platelets. In addition, defensins (40 microgram/ml) inhibited a in platelets n increase in the level of platelet cytoplasmic Ca-2+ caused by thrombin, ADP and lipopolysaccharide of Salmonella typhimurium endotoxin. The strongest inhibitory effect was observed in thrombin-stimulated platelets. It was shown that the effect of human defensins on the functional activity of platelets was determined by changes in the level of intracellular Ca-2+.