Cardiac mast cells: partial purification of guinea-pig atrial mast cells and release from them of histamine and leukotriene C4 by immune and non-immune stimuli.

The response of cardiac mast cells in enzymically dispersed guinea-pig atrial tissue to various immune and non-immune stimuli was studied. These cells were also partially purified by density-gradient centrifugation. The release of histamine, and in some experiments leukotriene C4, was measured. The cells responded strongly and consistently to the calcium ionophore A23187 but their response to other non-immune stimuli such as neuromuscular blockers and morphine (which are known to cause anaphylactoid reactions in human and other species) was relatively weak and inconsistent. Relatively weak responses were also obtained by immune stimuli in the following decreasing order: anti-IgG, antigen, histamine-releasing lymphokine and then the complement fragments C5a-desArg and C3a.