Table 8. Threshold concentration of that agonist for platelet activation and agonist-specific weight¹³,¹⁴,²¹.

Species	aj,crit	wj
ADP([apr])	1.00 × 106 nmol m−3	1
TxA2([apr])	1.20 × 106 nmol m−3	3.3
Thrombin([TB])	0.1 × 106 Um−3	30

It should be noticed that the threshold of the agonist may vary for some certain according to different experimental studies. For ADP see; refs ⁶⁹, ⁷³, ⁷⁴, ⁷⁵, ⁷⁶ for Thrombin see; refs ⁷⁷, ⁷⁸, ⁷⁹ for TxA₂ see refs ⁸⁰, ⁸¹, ⁸².