The rat isolated mast cell as a model for the study of calcium antagonists

EDTA-treated rat isolated mast cells were used to study the influence of Ca2+-antagonists on stimulus-secretion coupling. The concentration of Ca2+-effect curves for histamine release were parallelly shifted to the right when the cells were in the presence of Mg2+, La3+, verapamil or aminoglycoside antibiotics such as streptomycin, neomycin or gentamicin. The relative potency among the aminoglycoside was similar to that described in the literature for their action on the excitation-contraction coupling. The employed isolated mast cells preparation presented basic properties required for the study of coupled stimulus-secretion and represent an optimal model for the study of drugs which interfere with Ca2+ passage across cell membranes.