Calcium mobilization by arachidonic acid in trypanosomatids.

摘要: Abstract A recent report (Eintracht J, Maathai R, Mellors A, Ruben L. Calcium entry in Trypanosoma brucei is regulated by phospholipase 2 and arachidonic acid, Biochem J 1998;336:659–66) provided evidence that calcium bloodstream trypomastigotes via a signaling pathway involving -mediated generation of acid stimulation plasma membrane-located channel. Here we show Ca 2+ influx T. procyclic trypomastigotes, Leishmania donovani promastigotes cruzi amastigotes was also stimulated dose-dependent manner (50–400 nM) the amphiphilic peptide melittin. This effect blocked inhibitor 3-(4-octadecyl)-benzoylacrylic acid. The unsaturated fatty range 10–75 μM, induced mechanism sensitive to LaCl 3 . However, both melittin an increase [Ca ] i incubated -free medium implying mobilization from intracellular stores. hypothesis supported experiments showing promoted release acidocalcisomes these cells. results changes mitochondrial membrane potential, acridine orange transport across suggest addition possible channel-mediated process, concentrations used here, have other nonspecific effects on trypanosomatids membranes.