Fig. 6.
Concentration-dependent inhibition by MPSD of [3H]5-HT output in response to PKC activation.
Platelets were labeled with [3H]5-HT, permeabilized with digitonin, and incubated with 100 nM of PMA in the absence or presence of either MPSD or Ala-MPSD, as indicated in the legend to Figure 5. Inhibition of PMA-induced [3H]5-HT output by different concentrations of MPSD was expressed as a percentage of the [3H]5-HT output in the presence of PMA. Ala-MPSD at the higher concentration tested (10 μM) did not modify the secretory response induced by PMA. Values represent mean ± SEM of 8 different platelet preparations.