1) Investigación >
Artículos Publicados >

Por favor, use este identificador para citar o enlazar este ítem:

Título : Evaluation of the Presence of a Thapsigargin-Sensitive Calcium Store in Trypanosomatids Using Trypanosoma evansi as a Model
Autor : Mendoza, M.
Mijares, A.
Rojas, H.
Colina, C.
Cervino, Vincenza
DiPolo, R.
Benaím, Gustavo
Palabras clave : trypanosomatids
endoplasmic reticulum
sarcoplasmic–ER Ca(2+)
eukaryotic cells
Fecha de publicación : 2004
Citación : Vol. 90;No. 5 pp pp.1181–1183
Resumen : Ca(2+) plays an important role in the regulation of several important activities in different trypanosomatids. These parasites possess a Ca(2+) transport system in the endoplasmic reticulum (ER) involved in Ca(2+) homeostasis, which has been reported to be insensitive to thapsigargin, a classical inhibitor of the sarcoplasmic–ER Ca(2+) adenosine triphosphatase (ATPase) (SERCA) in most eukaryotic cells. However, currently there is a controversy regarding the existence of a thapsigargin- sensitive ER Ca(2+) store in these parasites. Therefore, we decided to explore the effect of this inhibitor using different methodological approaches. First, we selected Trypanosoma evansi as a parasite model to warrant the homogeneity of the population because this parasite has only a single life cycle, i.e., bloodstream-form trypomastigotes. Second, we compared the thapsigargin effect on Ca(2+) homeostasis by spectrophotometrical Ca(2+) measurements using 3 different approaches: wholecell populations, cells that have been permeabilized by treatment with digitonin, and intact single cells. Our results demonstrate that a low concentration of thapsigargin induces Ca(2+) release from intracellular Ca(2+) stores in this parasite, which can be observed independently of the method used. Furthermore, the addition of thapsigargin before or after nigericin did not abolish its effect, showing that thapsigargin acts specifically on the ER. In conclusion, our results indicate the presence of a nonmitochondrial thapsigargin-sensitive Ca(2+) store in T. evansi.
Descripción : M. Mendoza, Universidad Nacional Experimental Simón Rodríguez, Instituto de Estudios Científicos y Tecnológicos, Centro de Estudios Biomédicos y Veterinarios, Apartado Postal 47925, Caracas 1041A, Venezuela. e-mail:
ISSN : 1937-2345 (Online)
0022-3395 (Print)
Aparece en las colecciones: Artículos Publicados

Ficheros en este ítem:

Fichero Descripción Tamaño Formato
Mendoza et al J. Parasitol 2004 3 pag.pdf159.49 kBAdobe PDFVisualizar/Abrir

Los ítems de DSpace están protegidos por copyright, con todos los derechos reservados, a menos que se indique lo contrario.


Valid XHTML 1.0! DSpace Software Copyright © 2002-2008 MIT and Hewlett-Packard - Comentarios