Figure 4:

Cell surface expression and function of P2Y₁₂ R122H and V207A in transfected cells. A) Cell surface expression of HA-tagged P2Y₁₂ wild-type (WT), R122H and V207A was determined in transfected cells by ELISA using an anti-HA monoclonal antibody. Mean expression levels ± SEM in three independent experiments are presented, normalised to expression of WT P2Y₁₂. B) The ability of P2Y₁₂ WT, R122H and V207A to decrease cellular cAMP levels was determined in transfected cells by measuring residual cAMP by ELISA after incubation with the indicated concentrations of ADP. Data from three independent experiments are presented as the percentage inhibition (mean ± S. E. M) of the basal cAMP level in forskolintreated cells.