Figure 2

NTG Enhances Endothelial NO Production.

(A) Addition of NTG (5 μM) to L-NIO-treated ECs prevents the loss of endothelial NO production by L-NIO, as determined by NOA measurement of extracellular NO (n = 4 replicates per condition). Data normalized with respected to untreated control condition (con). **p < 0.01; ***p < 0.001. (B) Fluorescent images of ECs labeled with NO-sensitive dye (DAF-FM diacetate) and subsequent image analysis (bar graph; n = at least 30 cells) confirms that NTG-mediated increase in NO results from greater endothelial NO synthesis. Scale bar: 25 μm. ***p < 0.001. (C) Staining of U937 cell-EC co-cultures with anti-ICAM-1 and phalloidin (to label actin) and subsequent image analysis (bar graph; n ≥ 30 cells), as described in Materials and Methods, indicates that the anti-inflammatory effect of NTG (5 μM) correlates strongly with its ability to prevent ICAM-1 clustering induced by NO deficiency (L-NIO treatment). ***p < 0.001. Scale bar: 25 μm. Data are expressed as mean ± SEM.