Use of [3H]trimetoquinol as a radioligand in human platelets: interaction with putative endoperoxide/thromboxane A2 receptor sites.

@article{Ahn1988UseO,
  title={Use of [3H]trimetoquinol as a radioligand in human platelets: interaction with putative endoperoxide/thromboxane A2 receptor sites.},
  author={Chang Ho Ahn and Lane J. Wallace and D. D. Miller and Dennis R. Feller},
  journal={Thrombosis research},
  year={1988},
  volume={50 3},
  pages={
          387-99
        }
}
We have recently shown that trimetoquinol [1-(3,4,5-trimethoxybenzyl)-6,7-dihydroxy-1,2,3,4- tetrahydroisoquinoline; TMQ] is a potent and stereoselective [R(+)-isomer greater than S(-)-isomer] antagonist of aggregation induced by thromboxane A2 and stable epoxymethano PGH2 analogues (U46619; U44069) in human platelets. The present study was undertaken to characterize the pharmacological specificity of binding sites for racemic- [3H]TMQ in washed human platelets. Specific binding of [3H]TMQ… 
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References

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TLDR
These data, together with the ability of the TMQ stereoisomers to selectively inhibit TxA 2 -induced aggregation, suggest that TMQ is an inhibitor of endoperoxide or TXA 2 action, e.g. a thromboxane A 2 receptor antagonist.
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TLDR
Findings indicate that trans 13-APA binds to a specific site on the platelet membrane which presumably represents the thromboxane A2/prostaglandin H2 receptor.
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TLDR
Findings are consistent with the notion that these compounds all act as competitive antagonists at the level of the platelet TXA2/PGH2 receptor.
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TLDR
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TLDR
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TLDR
Observations show that the omega side chain of eicosanoid analogs can be substituted with a phenolic group, iodinated, and retain biological activity and may be utilized to study thromboxane A2 or prostaglandin H2 receptors.
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TLDR
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TLDR
Results show that expansion of the five- Membered ring of APA to the six-membered ring analogs (HAPA) led to a retention of potent inhibitory activity against U46619 in human platelets and rat vascular smooth muscle, and these azaprostanoic acid analogs act as selective endoperoxide (U46619)/thromboxane A2 antagonists in these two tissues.
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An unstable [t1/2 at 37 degrees = 32 +/- 2 (SD) sec] intermediate, thromboxane A2, was detected in the conversion of prostaglandin G2 into
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