Dose Response Relationships of Different Reagents for Platelet Aggregation

Background: Hemostasis in human body depends on a complicated series of events which actively involve blood platelets. Platelets exhibit diverse responses in a variety of agonists. In vivo, most of the agonists act in synergism, causing aggregation of platelets. Methods: The synergism between ADP – Epinephrine and Epinephrine – Collagen has been determined in this study by means of turbidometric method, which measures changes in optical density of platelet suspension. The study was carried out at the department of Hematology, Armed Forces Institute of Pathology, Rawalpindi. The subthreshold concentrations of each of the agonists were established with the help of dose response curve. By adding these agonists in subthreshold concentrations, the synergism between ADP – Epinephrine and Epinephrine – Collagen was determined. Results: The subthreshold levels of these agonists when combined showed the synergistic responses in causing platelet aggregation. Conclusion: The study brings to light that the optimal platelet aggregation does occur between the above mentioned pairs of agonists even when each of the agonist is added to the other in subthreshold doses.