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Analytical Techniques for Assaying Nitric Oxide Bioactivity
Published on: June 18, 2012
Norepinephrine depresses the nitric oxide production in the ascidian hemocytes
Cintia M de Barros1, Andressa de Abreu Mello, Silvana Allodi
1Laboratório Integrado de Morfologia, Pólo Barreto, Núcleo em Pesquisa e Desenvolvimento Sócio-Ambiental de Macaé, Campus Macaé, Universidade Federal do Rio de Janeiro, Brazil.
Abstract:
Norepinephrine (NE) is a neuro-hormone released by vertebrates and invertebrates during acute stress, and can influence their immune function. We found that NE depressed the production of nitric oxide (NO) by the hemocytes of ascidians. Our results with a fluorescent indicator for NO in assays using both NE and either α or β-antagonist revealed that NE down-regulated NO production by the ascidian hemocytes. Our data suggest that NE may be acting via specific hemocyte receptors to induce a decrease in immune function.
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