Effects of extracellular nucleotides on single cells and populations of human osteoblasts: contribution of cell heterogeneity to relative potencies.
Br J Pharmacol
; 120(5): 777-80, 1997 Mar.
Article
em En
| MEDLINE
| ID: mdl-9138681
ABSTRACT
1. Human osteoblasts responded to the application of extracellular nucleotides, acting at P2-receptors, with increases in cytosolic free calcium concentration ([Ca2+]i). 2. In populations of human osteoblasts, adenosine 5'-diphosphate (ADP) evoked a rise in [Ca2+]i with less than 40% of the amplitude of that induced by adenosine 5'-triphosphate (ATP). 3. ATP and uridine 5'-triphosphate (UTP) were applied to single human osteoblasts and induced [Ca2+]i rises of comparable amplitude in every cell tested. 4. However, from the results of single cell studies with ADP (and 2-methylthioATP (2-meSATP)) two groups of cells were delineated; one group responded to ADP (or 2-meSATP) with a rise in [Ca2+]i indistinguishable from that evoked by ATP; whereas the second group failed completely to respond to ADP (or 2-meSATP). 5. Therefore heterogeneity of receptor expression exists within this population of human osteoblasts. The limited distribution of the ADP-responsive receptor underlies the small response to ADP, compared with ATP, recorded in populations of human osteoblasts. This heterogeneity may reflect differences in the differentiation status of individual cells.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Osteoblastos
/
Uridina Trifosfato
/
Nucleotídeos de Adenina
/
Receptores Purinérgicos P2
Limite:
Humans
Idioma:
En
Revista:
Br J Pharmacol
Ano de publicação:
1997
Tipo de documento:
Article