-transparent.png){kind=logo}
Using aequorin-loaded rat platelets stimulated with collagen, we found two phases of Ca2+ mobilization, one coinciding with a shape change and the other with aggregation, which have not yet been detected in quin2-loaded platelets. U46619, a stable analogue of prostaglandin H2, induced only a shape change and a concomitant rapid rise in the cytoplasmic ionized calcium concentration ([Cai2+]). However, upon addition of U46619 to platelets previously stimulated with collagen in the presence of indomethacin, a rapid increase in [Cai2+] and a shape change occurred, and, after about 1 min, second increase in [Cai2+] and aggregation occurred. The actions of U46619 were inhibited by an antagonist for the thromboxane A2 (TXA2) receptor. These results suggest that the collagen-induced shape change is initiated by TXA2-induced Ca2+ mobilization, and aggregation is induced by the secondary Ca2+ mobilization induced by TXA2 and the occupation of the receptor by collagen.
T Nakano, and
A Terawaki, and
H Arita
February 1985,
The Journal of biological chemistry,
T Nakano, and
A Terawaki, and
H Arita
January 1986,
Methods in enzymology,
T Nakano, and
A Terawaki, and
H Arita
January 1989,
Journal of lipid mediators,
T Nakano, and
A Terawaki, and
H Arita
March 2001,
Tanpakushitsu kakusan koso. Protein, nucleic acid, enzyme,
T Nakano, and
A Terawaki, and
H Arita
February 1993,
The Biochemical journal,
T Nakano, and
A Terawaki, and
H Arita
September 1987,
Blood,
T Nakano, and
A Terawaki, and
H Arita
December 1983,
Biochemical and biophysical research communications,
T Nakano, and
A Terawaki, and
H Arita
January 1989,
Methods in enzymology,
T Nakano, and
A Terawaki, and
H Arita
November 1986,
Proceedings of the National Academy of Sciences of the United States of America,
T Nakano, and
A Terawaki, and
H Arita
November 1985,
Biochemistry,
