DAF-2 NO images under static conditions in bEnd3 monolayer with ECs only (A), in bEnd3 monolayer with adherent TCs (B), and in TCs only (C). Left image in A is that after 45-min DAF-2 DA loading, and right image is that for 30 min later. Left image in B is for DAF-2 NO 30 min after 45-min DAF-2 DA loading in bEnd3 monolayer with adherent TCs, middle image is for adherent TCs, and right image is the overlay of the left and middle images. Left image in C is for DAF-2 NO 30 min after 45-min DAF-2 DA loading in TCs, and the right one is for TCs. The dotted line-enclosed oval-shaped regions are ROIs (∼40 μm for the long axis and 25 μm for the short axis) for NO production quantification in ECs without adherent TCs and the same-sized solid line-enclosed ROIs for those in ECs with adherent TCs or that in TCs. Four regions of ∼750 × 560 μm were taken from each experiment. Twenty to thirty ROIs for each type were chosen on each region. D: comparison of NO production in ECs and TCs under static conditions. The averaged DAF-2 intensity is for the ROIs over 3 experiments for each case. *P < 0.05, compared NO production in TCs with that in ECs. Values are means ± SE.