TY - JOUR
T1 - A major role for P2X(I) receptors in the early collagen-evoked intracellular Ca2+ responses of human platelets
AU - Fung, C. Y. Eleanor
AU - Brearley, Charles A.
AU - Farndale, Richard W.
AU - Mahaut-Smith, Martyn P.
PY - 2005/7
Y1 - 2005/7
N2 - In the platelet, ATP-gated P2X1 receptors have been reported to amplify functional responses to collagen,however the relative importance of early Ca2+ mobilisation events is unknown. We now report that selective desensitisation of P2X1 receptor activity leads to a major reduction in the initial intracellular Ca2+ responses to a wide range of collagen concentrations (0.25–2 µ g ml-1). Peak [Ca2+] i increases were reduced to 8.5 and 55% of control, and the maximum rate of rise was reduced to 12 and 33% of control,at low and high collagen concentrations,respectively. This P2X 1 -dependent acceleration and enhancement of collagen-stimulated Ca2+ responses was not observed in the absence of extracellular Ca2+.These results demonstrate a major role for ATP-gated Ca2+ influx in the early collagen-evoked Ca2+ signals and can at least partly explain the important contribution of P2X1 receptors to arterial thrombosis.
AB - In the platelet, ATP-gated P2X1 receptors have been reported to amplify functional responses to collagen,however the relative importance of early Ca2+ mobilisation events is unknown. We now report that selective desensitisation of P2X1 receptor activity leads to a major reduction in the initial intracellular Ca2+ responses to a wide range of collagen concentrations (0.25–2 µ g ml-1). Peak [Ca2+] i increases were reduced to 8.5 and 55% of control, and the maximum rate of rise was reduced to 12 and 33% of control,at low and high collagen concentrations,respectively. This P2X 1 -dependent acceleration and enhancement of collagen-stimulated Ca2+ responses was not observed in the absence of extracellular Ca2+.These results demonstrate a major role for ATP-gated Ca2+ influx in the early collagen-evoked Ca2+ signals and can at least partly explain the important contribution of P2X1 receptors to arterial thrombosis.
U2 - 10.1160/TH04-11-0732
DO - 10.1160/TH04-11-0732
M3 - Article
VL - 94
SP - 37
EP - 40
JO - Thrombosis and Haemostasis
JF - Thrombosis and Haemostasis
IS - 1
ER -