A comparative study of histamine secretion from rat peritoneal and pleural mast cells

The effects of various histamine liberators and inhibitors on isolated rat peritoneal and pleural mast cells have been compared. The pleural cells showed an increased reactivity to challenge with antigen following passive, but not active, sensitization and were more responsive to challenge with anti-IgE. Phosphatidyl serine enhanced the secretion from both cell types. Peritoneal and pleural cells exhibited virtually identical responses after treatment with chemical secretagogues in the presence of exogenous calcium, but the peritoneal cells were significantly more reactive to stimulation with basic inducers in the absence of the cation. Anaphylactic histamine secretion was comparably inhibited by a number of anti-allergic drugs but the peritoneal cells were rather more sensitive to inhibition by dibutyryl cyclic AMP. These results are discussed in terms of the general functional heterogeneity of mast cells from different sources.