Figure 4.

NEM effect on Om-DNP transcytosis. (A) Graphic representation of the amount of Om-DNP, expressed as protein equivalents, transported in the presence of NEM (broken line) and in the absence of NEM (continuous line) in perfused murine hearts. Tracer amounts were determined in 8–10 consecutive experiments (4–6 mice per experiment), and ELISAs were performed in duplicates for three different dilutions. Tracer perfusions were for 15 min as described in the text. Every point on the graphs is a mean value of ≈35 determinations with standard deviation given. (B) An electron micrograph taken from one of the mice used to quantitate Om-DNP transcytosis in the presence of NEM. The normal endothelial morphology, the lack of any detectable structural alteration, and the drastic reduction in labeling of endothelial caveolae and perivascular spaces (compare with Fig. 2 B, C, E, and F) at the end of a 20-min exposure to 1 mM NEM are illustrated by this micrograph. (Bar = 84 nm.)