Kinetic study of the plasma-membrane potential in procyclic and bloodstream forms of Trypanosoma brucei brucei using the fluorescent probe bisoxonol

摘要: The characteristics of the plasma-membrane potential procyclic and bloodstream forms Trypanosoma brucei (cultured cells) were investigated using fluorescent anionic probe bisoxonol. Observation a stable representative in resting state required careful washing, centrifugation maintenance cells at room temperature before measurement. Bloodstream more prone to depolarization during washing 4 degrees C than cells. higher fluorescence observed presence long slender shows that is negative insect form. Healthy dilute can sustain their for hours external glucose. high K+ concentration medium did not promote by itself either type cell. Study bisoxonol as function time allowed us follow kinetics action metabolic inhibitors various ions. o-Vanadate (1 mM) was found depolarize bloodstream-form rapidly but only phosphate-free NaCl buffer. Omeprazole strophanthidin also specifically depolarized trypanosomes. However, NN'-dicyclohexylcarbodi-imide both types cell, Bloodstream-form trypanosomes appear use mainly vanadate-sensitive Na+ pump maintain Na+-diffusion gradient. most ATPase tested had little or no effect on procyclics suggesting this form trypanosome may rely several regulation mechanisms.