Biological and Biomedical Sciences
Our previous studies have shown that subthreshold concentrations of two platelet agonists exert synergistic effects on platelet aggregation. Here we studied the mechanism of synergistic interaction of 5-hydroxytryptamine (5-HT) and epinephrine mediated platelet aggregation. We show that 5-HT had no or little effect on aggregation but it did potentiate the aggregation response of epinephrine. The synergistic interaction of 5-HT (1-5 microM) and epinephrine (0.5-2 microM) was inhibited by alpha2-adrenoceptor blocker (yohimbine; IC50= 0.4 microM), calcium channel blockers (verapamil and diltiazem with IC50 of 10 and 48 mM, respectively), PLC inhibitor (U73122; IC50=6 microM) and nitric oxide (NO) donor, SNAP (IC50=1.6 microM)). The data suggest that synergistic effects of platelet agonists are receptor-mediated and occur through multiple signalling pathways including the activation PLC/Ca2+ signalling cascades.
Experimental and Molecular Medicine
Shah, B. H.,
Qureshi, K. A.,
Ujan, V. A.,
Yakoob, M. Y.,
Saeed, S. A.
(1999). Co-activation of Gi and Gq proteins exerts synergistic effect on human platelet aggregation through activation of phospholipase C and Ca2+ signalling pathways. Experimental and Molecular Medicine, 31(1), 42-46.
Available at: https://ecommons.aku.edu/pakistan_fhs_mc_bbs/436
Creative Commons License
This work is licensed under a Creative Commons Attribution-Noncommercial 3.0 License