Nitric Oxide Synthase Trafficker, abbreviated as NOSTRIN, is a protein that plays a role in the regulation of nitric oxide synthase (NOS) activity. NOSTRIN is involved in the internalization and trafficking of endothelial NOS (eNOS) from the plasma membrane to intracellular compartments, which affects the production of nitric oxide (NO). NO is a signaling molecule that has a variety of physiological functions, including the regulation of blood pressure and vascular tone. By modulating the localization and activity of eNOS, NOSTRIN can influence these processes. NOSTRIN is expressed in various tissues, with particularly high levels in the endothelium, and its expression is regulated by factors such as shear stress and inflammatory cytokines. Alterations in NOSTRIN function have been implicated in several cardiovascular diseases.Caveolin 1 (CAV1) is a protein that is known to interact with NOSTRIN. This interaction is significant in various cellular processes, including the regulation of lipid metabolism and signal transduction pathways. Thus a functional ELISA assay was conducted to detect the interaction of recombinant mouse NOSTRIN and recombinant mouse CAV1. Briefly, NOSTRIN was diluted serially in PBS with 0.01% BSA (pH 7.4). Duplicate samples of 100 μl were then transferred to CAV1-coated microtiter wells and incubated for 1h at 37℃. Wells were washed with PBST and incubated for 1h with anti-NOSTRIN pAb, then aspirated and washed 3 times. After incubation with HRP labelled secondary antibody for 1h at 37℃, wells were aspirated and washed 5 times. With the addition of substrate solution, wells were incubated 15-25 minutes at 37℃. Finally, add 50 μL stop solution to the wells and read at 450/630nm immediately. The binding activity of recombinant mouse NOSTRIN and recombinant mouse CAV1 was shown in Figure 1, the EC50?for this effect is 0.10ug/mL.