Morphological changes and membrane potential of human granulocytes under influence of chemotactic peptide and/or echo-virus,type 9

Summary The membrane potential,E_m, of human granulocytes (PMNs), was recorded using glass microelectrodes. The membrane potentialE_m exhibited potential fluctuations accompanied by characteristic changes of cell shape. The periodic potential fluctuations (7-s, 70-s, and 260-s periodicities) ascertained by the autocorrelation technique, suggested the existence of an internal clock. The chemoattractant f-Met-Leu-Phe (FMLP) had no influence on the periodicities, whereas the amplitudes of the fluctuations were increased by it. Treatment of PMNs with Echo 9 virus also resulted in hyperpolarization. The 70-s periodicity disappeared under virus treatment indicating a virus-induced change of the internal program and loss of chemotactic activity.Abbreviations ACF Autocorrelation function - Echo 9 AB virus Echo virus, type 9, strain A Barty - E_m Membrane potential - FMLP N-formyl-methionyl-leucyl-phenylalanine - PMN Human polymorphonuclear granulocyte - t₁,t₂,t₄ Characteristic periodic length - t₃ Aperiodic decay time