uNOS Products

Nitric Oxide (NO) is an inorganic, gaseous free radical that carries a variety of messages between cells including vasorelaxation, neurotransmission and cytotoxicity. NO is produced by a Nitric Oxide Synthase (NOS) family of enzymes which oxidizes the amino acid L-arginine to form L-citrulline and NO.Two constitutive forms, brain NOS (bNOS) & endothelial cell NOS (eNOS), and one inducible form (iNOS), have been cloned showing regions for binding of calmodulin, NADPH, FAD, and FMN. iNOS has been found in a variety of tissues including macrophages, hepatocytes, synoviocytes, and smooth muscle cells. It is induced after exposure to cytokines such as interferon-* (IFN), tumor necrosis factor, interleukin-1, interleukin-2, and lipopolysaccarides (LPS). After cytokine induction, iNOS has a delayed response followed by high levels of NO produced over a long period of time. eNOS and bNOS share ~50% sequence homology, and their activity depends on binding to the calcium/calmodulin complex. Both constitutive isoforms respond immediately to increased levels of calcium to produce low levels of NO over a short period of time. bNOS has been found in neurons, peripheral nerve cells, macula densa & pancreatic islet cells. eNOS is capable of synthesizing NO in vascular endothelial cells where it appears to play an important role in the control of vasotension and platelet aggregation.