Expression of Adhesion Molecules on the Surface of Activated Platelets is Diminished by PGI2-analogues and an NO (EDRF)-Donor: A Comparison Between Platelets of Healthy and Diabetic Subjects
| Autor: | Kaufmann L, Diethelm Tschöpe, B. Schwippert, P. Rösen |
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| Rok vydání: | 1994 |
| Předmět: | |
| Zdroj: | Platelets. 5:45-52 |
| ISSN: | 1369-1635 0953-7104 |
| DOI: | 10.3109/09537109409006040 |
| Popis: | Adhesion molecules such as P-selectin (CD 62), glycoprotein (CP) 53 (CD63) and thrombospondin play a decisive role in the thrombogenic transformation of platelets. Here we present evidence obtained using flow cytometric analysis that the PGI(2)-mimetics iloprost and taprostene, and an NO (EDRF)donor (SIN-1) are able to inhibit the expression of P-selectin, GP 53 and thrombospondin on human platelets activated by submaximal concentrations of thrombin. Since the half-maximal concentrations for inhibition of antigen expression (0.15 nM for iloprost, 3.0-5.3 nM for taprostene) are much lower than for activation of adenylate cyclase (1.4 nM for iloprost and 29.4 nM for taprostene) our data suggest that the occupation of a small number of PGI(2)-receptors is sufficient to inhibit the thrombogenic transformation and that spare PGI(2)-receptors are present on human platelets. In diabetes, the EC(50) for inhibition of expression of platelet antigens is shifted to higher concentrations suggesting that platelets from type 1 diabetic patients are partly resistant to PGI(2). Since the dose dependent increase in c-AMP by iloprost is not changed and intraplatelet c-AMP is elevated in platelets of diabetic patients, we assume that steps in the activation cascade subsequent to activation of adenylate cyclase are disturbed in diabetes. |
| Databáze: | OpenAIRE |
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