RESUMEN

The effect of purines on the activation and aggregation of thrombocytes in rats and rabbits was studied by the method of small-angle light scattering. The EC50 values of ADP, inducing the activation and aggregation of thrombocytes, reflect the sequence of the agonist action on various receptors: P2X1, 20-40 nM; P2Y1, 90-110 nM; P2YADP, 120-240 nM. It was demonstrated that ADP behaves as partial agonist not only with respect to P2X1 receptors, but with respect to P2Y1 receptors as well. Thrombocytes activated by 20 nM ADP or 100-nM ATP pass into a refracter state in the absence of further stimulation. The reaction halftime is tau 1/2 = 6.0 +/- 0.2 min for the cells activated with ADP and tau 1/2 = 16.5 +/- 0.2 min for ADP.

Asunto(s)

Plaquetas/efectos de los fármacos , Nucleótidos de Purina/farmacología , Agonistas del Receptor Purinérgico P2 , Adenosina Difosfato/farmacología , Adenosina Difosfato/fisiología , Adenosina Trifosfato/farmacología , Adenosina Trifosfato/fisiología , Animales , Plaquetas/metabolismo , Luz , Masculino , Activación Plaquetaria/efectos de los fármacos , Agregación Plaquetaria/efectos de los fármacos , Conejos , Ratas , Ratas Wistar , Receptores Purinérgicos P2X , Receptores Purinérgicos P2Y1 , Dispersión de Radiación