PECULIARITIES OF NEUTROPHIL ACTIVATION IN VITRO
I. G. Gerasimov, D. Y. Ignatov
Research Institute of Family Medical Problems, Donetsk Medical State University, 83048 Donetsk, the Ukraine;
e-mail: DmiL@rambler.ru
Kinetics of spontaneous and induced reactions of Nitroblue tetrazolium (NBT) restoration by neutrophils was
investigated in vitro. The index of activated neutrophils (IAN), commonly characterizing cell activation degree depending on the
reaction time (t), was described by the equation: IAN = [NBT0](1 - exp[-k1t]) + k0t;
where (NBT0) is intracellular concentration of NBT, which reflects membrane permeability, k1 and
k0 - speed constants of the first and zero order reactions, characterizing, respectively, stimulation and spontaneous
activities of enzymatic systems involved in NBT restoration. We detected the ability of heparin (2.0-7.5 mkg/ml) or chond-rotin sulphate
(0.25-2.5 mkg/ml) to activate neutrophils and presumably to maintain in vivo their spontaneous activity. The values of kinetics
equation parameters enable us to speculate about relative hyper-, hypo- and normal function of neutrophils, related to the functional state
of the whole organism. The value of [NBT0] changes from 8 to 103 conventional units, and a high correlation exists between
this index and the reaction speed constants, differing in stimulated and spontaneously activated cells. The latter are represented by
neutrophils only, which, as shown before, produce active forms of oxygen, used, probably, not for phagocytosis needs. The share of
such cells makes approximatelity 30-40 % of the neutrophil recirculating pool, and positively correlates with [NBT0]
(r = 0.58; P < 0.05). This is determined by a very high membrane permeability of this neutrophil subpopulation. The detected
different spontaneous and stimulated ability, various membrane permeability and enzyme system activity confirm the neutrophil functional
unequality, which defines their activation peculiarity.
Back
Contents
Main
|
