Potentiation by NNKY5-5 of platelet aggregation induced by other agonists. Light scatter (LS) was divided into two portions by intensity. Changes in LS between 0.2 to 2V, which represents aggregates consisting less than 150 cells, are shown as closed dots, and LS that represents larger aggregates shown as open dots. Changes in light transmission (LT) is shown as solid lines. (A) NNKY5-5 alone (10 μg/mL) induced moderate LS of small size and a change in LT of only around 10%. ADP (0.5 μmol/L) or PAF (10 nmol/L) induced only primary aggregation, which gradually disappeared (B and D, respectively). Addition of NNKY5-5 (10 μg/mL) 2 minutes before ADP or PAF enhanced platelet aggregation and prolonged its duration (C and E, respectively). (F ) shows a typical pattern of ADP-induced platelet aggregation, detected by LS, which can quantitatively measure the size and number of platelet aggregates. It shows changes in LS and LT induced by 5 μmol/L ADP, which induced full aggregation. ADP first induced the formation of small aggregates (closed dots), followed by an increase in larger aggregates (open dots) with a concomitant decrease in small aggregates. LS is shown in arbitary units. Representative data from at least four experiments are shown.