Fig. 10.

a P2X receptor-mediated inward currents are absent in P2X1 receptor-deficient mice megakaryocytes. α,β-Methylene ATP (α,β-meATP; 10 μM) evoked rapid transient inward currents in wild-type (+/+) megakaryocytes; these were absent in megakaryocytes from P2X1 receptor-deficient (−/−) mice. Bar indicates period of drug application. (Reproduced from [280] with permission from John Wiley and Sons.) b Effect of pulse amplitude on the depolarization-evoked [Ca²⁺]_i increase during stimulation of P2Y receptors. [Ca²⁺]_i responses of rat megakaryocytes to ADP (1 μM, horizontal bar) and step depolarizations from a holding potential of −75 mV. The effect of depolarization during ADP application was assessed after the agonist-evoked increase had settled to a raised plateau level. Effect of increasing the amplitude of the depolarizing step in 5 mV increments up to 75 mV. (Reproduced from [393] with permission from John Wiley and Sons.)