Stimulation of histamine synthesis in rat mast cells by compound 48/80 in vitro

The histamine content of rat peritoneal fluid cells is doubled within 20 min by 0.5 microgram/ml of compound 48/80. Histamine catabolism inhibitors do not reproduce this effect; cells pre-incubated with alpha-fluoromethylhistidine are unresponsive to compound 48/80 which therefore activates pre-formed histidine decarboxylase rather than 'inducing' it. Non-mast cells showed no change after treatment with compound 48/80.