Figure 4.
NO production by coronary arterioles in the presence and absence of OxLDL. NO production was measured by chemiluminescence detection of nitrite. The resting NO production (Basal; n=6) was not altered by OxLDL (0.5 mg protein/ml; n=6). In the presence of OxLDL (0.5 mg protein/ml; n=4), the NO production stimulated by serotonin (0.1 μM; n=4) was significantly inhibited. In the presence of arginase inhibitor DFMO (0.4 mM), the serotonin-induced NO production (0.1 μM; n=5) was comparable to that without DFMO and the OxLDL (0.5 mg protein/ml; n=5) did not affect this NO production. *P<0.05 vs. Basal.