FIGURE 4.

Polyamines were released through exocytosis from BMMCs. a, time courses of spermine (top), spermidine (middle), and histamine (bottom) release from BMMCs in the presence (closed circles) or absence (open circles) of antigen. Data are means ± S.E. (error bars); n = 3–4 technical replicates. Essentially similar data were obtained from biological replicates (data not shown). b, calcium dependence of polyamines and histamine release. BMMCs were incubated in the presence or absence of 1 mm EGTA. c, time courses of spermine (left) and spermidine (right) release from BMMCs in the presence (closed circles) or absence (open circles) of 2 μm calcium ionophore (A23187). d, effects of 1 μm bafilomycin A₁ on polyamine release from BMMCs. BMMCs were pretreated with inhibitors for 2 h, followed by assay of IgE/antigen-evoked spermine (left) and spermidine (right) secretion. e, temperature dependence of polyamine release. BMMCs were incubated and assayed for IgE/antigen-evoked spermine (left) and spermidine (right) secretion at the indicated temperature. f, effect of tetanus toxin (TeNT) on polyamine release from BMMCs. BMMCs were treated with 10 μg/ml TeNT for 36 h and assayed for IgE/antigen-evoked spermine (left) and spermidine (right) secretion. Data are means ± S.E.; n = 3–4 technical replicates. Essentially similar data were obtained from biological replicates (data not shown). *, p < 0.05; **, p < 0.01; ***, p < 0.001; N.D., not detected.