FIGURE 9.

Thrombin-promoted ATP release and inositol phosphate formation in primary HBE cells. A, well differentiated primary HBE cells were incubated for 5 min with 30 nm thrombin (basolateral), 100 μm UTP (apical), or vehicle; ATP released to the apical or basolateral (BL) medium was quantified, as indicated under “Experimental Procedures.” B, HBE cells were preincubated bilaterally (1 h) with 1 μm H1152, 10 μm ML-7 or1 μm CBX, and apical ATP release was measured after 5-min incubation with 30 nm thrombin (basolateral addition) or vehicle. C, [³H]inositol-labeled HBE cells were incubated for 20 min in the presence of vehicle, 30 nm thrombin (basolateral addition), 100 μm UTP (apical addition), and in the absence or presence of 5 U/ml apyrase (apical addition). The resulting [³H]inositol phosphates were quantified as indicated under “Experimental Procedures.” The data (mean ± S.D.) represent the net increase in counts above background, and they are representative of two separate experiments with independent cultures performed each with quadruplicate samples. *, indicates significant difference between apyrase-treated versus non-treated cultures, p < 0.01.