Extracellular ATP4- permeabilizes thymocytes not only to cations but also to low-molecular-weight solutes.
Eur J Pharmacol
; 181(1-2): 111-8, 1990 May 31.
Article
en En
| MEDLINE
| ID: mdl-2387318
Extracellular ATP increases the free cytosolic calcium concentration ([Ca2+]i) of thymocytes by changing the membrane permeability to divalent cations: (1) no [Ca2+]i elevation is observed in the absence of extracellular calcium and (2) ATP also promotes Mn2+ entry into thymocytes, as shown by a stimulated quench of the fluorescence of Quin2-loaded cells. Using 1-(4-trimethylammoniumphenyl)-6-phenyl-1,3,5- hexatriene, a dye which usually does not pass through membranes, we showed that ATP permeabilizes thymocyte membranes not only to cations but also to low-molecular-weight solutes. The ATP effect is dose-dependent, specific and reversible; ATP4- appears to be the active species and probably acts through specific receptor(s). Both medullary and cortical thymocytes respond to ATP whereas splenocytes do not; this shows that the ATP effect is restricted to certain populations of lymphocytes. The thymoma-derived cell line, EL-4, the permeability of which is also sensitive to ATP, could provide a useful model for studying the putative ATP4- receptor(s) of thymocytes.
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Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Linfocitos T
/
Cationes
/
Permeabilidad de la Membrana Celular
/
Adenosina Trifosfato
Límite:
Animals
Idioma:
En
Revista:
Eur J Pharmacol
Año:
1990
Tipo del documento:
Article
País de afiliación:
Francia
Pais de publicación:
Países Bajos