|
|
Previous Article | Table of Contents | Next Article 
Expression of Prostacyclin Receptor in Human Megakaryocytes
Yutaka Sasaki,
Takayuki Takahashi,
Issei Tanaka,
Kishiko Nakamura,
Yoshiaki Okuno,
Osamu Nakagawa,
Shuh Narumiya, and
Kazuwa Nakao
From the Department of Medicine and Clinical Science, and the Department of Pharmacology, Kyoto University Graduate School of Medicine, College of Medical Technology, Kyoto University, Kyoto; and the Department of Immuno-Hematology, Kobe City General Hospital, Kobe, Japan.
Prostacyclin (prostaglandin I2, PGI2) is a potent vasodilator and inhibitor of platelet aggregation. Although it is well known that the specific receptor for prostacyclin (PGI2-R) is abundantly expressed on platelets, PGI2-R expression in megakaryocytes is poorly understood. In this study, we examined its expression in leukemic or normal megakaryocytes. PGI2-R mRNA was expressed in human leukemic cell lines of megakaryocytic nature as evaluated by Northern blot analysis. Phorbol 12-myristate 13-acetate (PMA), interleukin-1 (IL-1), IL-3, IL-6, granulocyte-macrophage colony-stimulating factor (GM-CSF ), thrombopoietin (TPO), and tumor necrosis factor- (TNF- ) enhanced PGI2-R mRNA expression. The enhancement of PGI2-R expression by PMA and TPO was associated with the upregulation of platelet factor 4 or glycoprotein IIb mRNA expression. Iloprost, an agonist of prostacyclin, induced significant cyclic (c)AMP synthesis in these leukemic cells indicating that interaction of PGI2-R and its ligand can induce postreceptor signal transduction. Furthermore, iloprost-induced cAMP synthesis was enhanced by the pretreatment with PMA or the cytokines that promoted PGI2-R expression. PMA and TPO also increased the specific binding of [3H]iloprost to these cells. Pooled normal megakaryocytic colonies from TPO-containing semisolid culture of purified human CD34+ cells expressed PGI2-R, which were increased as the megakaryocytes matured with the peak expression before proplatelet formation, as evaluated by semiquantitative reverse transcription-polymerase chain reaction (RT-PCR). These results indicate that PGI2-R is expressed in human megakaryocytes and is upregulated by cytokines involved in thrombopoiesis or inflammation. Also, it was indicated that megakaryocytic maturation accompanies enhancement of PGI2-R expression.
Blood, Vol. 90 No. 3 (August 1), 1997:
pp. 1039-1046
© 1997 by The American Society of Hematology.

CiteULike Connotea Del.icio.us Digg Reddit Technorati What's this?
This article has been cited by other articles:

|
 |

|
 |
 
K. Hocherl, C. Schmidt, B. Kurt, and M. Bucher
Activation of the PGI2/IP System Contributes to the Development of Circulatory Failure in a Rat Model of Endotoxic Shock
Hypertension,
August 1, 2008;
52(2):
330 - 335.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
E. den Dekker, G. Gorter, J. W. M. Heemskerk, and J.-W. N. Akkerman
Development of Platelet Inhibition by cAMP during Megakaryocytopoiesis
J. Biol. Chem.,
August 2, 2002;
277(32):
29321 - 29329.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
E. den Dekker, J. W.M. Heemskerk, G. Gorter, H. van der Vuurst, J. Donath, C. Kroner, K. Mikoshiba, and J.-W. N. Akkerman
Cyclic AMP Raises Intracellular Ca2+ in Human Megakaryocytes Independent of Protein Kinase A
Arterioscler. Thromb. Vasc. Biol.,
January 1, 2002;
22(1):
179 - 186.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
S. Madoiwa, N. Komatsu, J. Mimuro, K. Kimura, M. Matsuda, and Y. Sakata
Developmental Expression of Plasminogen Activator Inhibitor-1 Associated With Thrombopoietin-Dependent Megakaryocytic Differentiation
Blood,
July 15, 1999;
94(2):
475 - 482.
[Abstract]
[Full Text]
[PDF]
|
 |
|
| |