Figure 4.

Chelerythrine inhibits both ATP- and PMA-induced PLD activity. [³H]oleic acid-labelled CLL B-lymphocytes were incubated in KCl medium containing 1 μM BaCl₂ in the absence or presence of 10 μM chelerythrine for 15 min prior to the addition of 500 μM ATP or 0.1 μM PMA for a further 15 min at 37°C. The data are presented as means ±s.e.m. from five separate experiments (^*P<0.03, ^**P<0.05, chelerythrine versus control).