Intracellular alkalinisation in Vero cells parasitised by Trypanosoma cruzi

Citation
N. Rodriguez-cabezas et al., Intracellular alkalinisation in Vero cells parasitised by Trypanosoma cruzi, INT J PARAS, 28(12), 1998, pp. 1841-1851
Citations number
37
Categorie Soggetti
Biology,Microbiology
Journal title
INTERNATIONAL JOURNAL FOR PARASITOLOGY
ISSN journal
00207519 → ACNP
Volume
28
Issue
12
Year of publication
1998
Pages
1841 - 1851
Database
ISI
SICI code
0020-7519(199812)28:12<1841:IAIVCP>2.0.ZU;2-Y
Abstract
We studied the intracellular pH of Vero cells parasitised by Trypanosoma cr uzi, using different methods: fluorimetric measurement after labelling the cells with the pH-sensitive intracellular fluorescent dye 2', 7',-bis-(2-ca rboxyethyl)-5-(and-6)-carboxyfluorescein, acetoxymethyl ester; flow cytomet ry; and image analysis after staining the cells with neutral-red vital stai n. The results show that the intracellular pH of the parasitised cells rose in comparison with that of the uninfected control cells. A study of the po pulation of parasitised cells made by flow cytometry allowed us to subdivid e the cells from the infected cultures into two populations according to th eir pH as obtained by fluorimetric measurements. Image analysis showed that the cell cytoplasm was more alkaline in the vicinity of the sites containi ng parasites. Treatment of the parasitised cells with amiloride, ouabain, o r with 4,4'-diisothiocyano-2,2'-stilbene disulphate consistently lowered th e pH Values of the parasitised cells, but not sufficiently to return to the values of the non-parasitised control cells. When the control cells were s ubject to similar treatments with the inhibitors, only amiloride acidified the cytoplasm to any extent. The basification undergone by the parasitised cells was independent of the transport systems and may be a consequence of the release of NH4+ by the intracellular amastigotes. (C) 1998 Australian S ociety for Parasitology. Published by Elsevier Science Ltd. All rights rese rved.