Dopamine Potentiation of Calcium Ionophore, A-23187-Induced Platelet Aggregation
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Dopamine (DA) is widely studied neurotransmitter and has been implicated in several diseases. Although the effects of DA on human or rabbit platelet function have been reported (Braunsein et al., 1977), little is known about the role of DA in platelet aggregation. More recently DA1 and DA2 receptors, which couple with the guanine nucleotide binding proteins (G-proteins) have also been identified on platelets (Watson and Arkinstall, 1994). In our recent studies, we have shown that synergistic action of different agonists, when added together in subthreshold concentrations, plays a trivial role in the activation of platelets. The best known examples are ADP and collagen, thrombin and ADP, epinephrine and ADP and 5-HT and epinephrine (Heemskerk and Sage, 1994; Shah and Saeed, 1995).
KeywordsPlatelet Aggregation Tyrosine Phosphorylation Platelet Rich Plasma Human Platelet Calcium Ionophore
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