(A) NO production level in PECAM-1 +/+ and PECAM-1 −/− bEND cells were measured by DAF-FM assay as previously described [185]. (B) Phosphorylation level of Ser1177, Thr495, and Ser113 sites of eNOS were analyzed by Western blot analysis as previously described [185]. All antibodies were from Cell Signaling (Boston, MA). Anti-PECAM-1 was from R&D Systems (Minneapolis, MN) and anti-eNOS was from Santa Cruz (Santa Cruz, CA). Please note diminished production of NO in PECAM-1−/− bEND cells perhaps as a result of increased Ser113 and Thr495 phosphorylation despite similar expression of eNOS and Ser1177 phosphorylation as PECAM-1+/+ bEND cells. (S.Park, CM Sorenson and N. Sheibani, unpublished work)