The response of human PMN zeta potential to selected ligands of the cAMP signal pathway under low-dose β-radiation

Abstract

The objective of this study was to examine the zeta potential (ZP) response of human neutrophils to selected ligands of the cAMP signalling pathway under low-dose β-radiation (LDBR). ZP was calculated from the electrophoretic mobility (EPM) of the cells. Cells were irradiated at a dose rate of 10 µGy/hour for one hour. Irradiation of cell suspensions was conducted by adding appropriate aliquots of 14C-leucine to the incubation medium. EPM measurements were carried out in a radiation field. It was demonstrated that the LDBR and agonists of the AC system are capable of increasing the negative surface charge of human neutrophils. Conversely, the antagonist propranolol has been shown to reduce it. Furthermore, it has been demonstrated that radiation affects the response of the membrane ZP to some ligands of the AC pathway and vice versa. Therefore, LDBR can significantly alter the sensitivity of cells to drugs acting on the targets of these ligands. These results do not permit the conclusion that the effect of LDBR on ZP is mediated through the targets with which the studied ligands interact, since any of its components may undergo structural rearrangement, thereby altering the structural organisation of neutrophil membranes in the LDBR field.