Aquatic Biotechnology Department, Animal Biotechnology Division, Center for Genetic Engineering and Biotechnology, P.O. Box 6162, Havana 10600, Cuba.
Fish Shellfish Immunol. 2010 Sep;29(3):513-20. doi: 10.1016/j.fsi.2010.05.004. Epub 2010 May 25.
To date, published in-vivo studies on the action of the PACAP in fish are few and these are concerned with reproduction, brain development and feeding behavior. Recently, we demonstrated for the first time that PACAP, apart from its neuroendocrine role, influences immune functions in fish larvae. In this work, we have evaluated the effects of recombinant Clarias gariepinus PACAP administration by intraperitoneal injection on important immune parameters in juvenile fish. We observed that a single injection of the recombinant peptide (0.1 microg per g of body weight) was able to increase the nitric oxide synthase-derived metabolites (NOS) and total immunoglobulin M (IgM) concentration in serum of juvenile catfish C. gariepinus and tilapia Orechromis niloticus respectively, after 24 h of its administration. In addition, our results showed that recombinant PACAP increases IgM, NOS and lysozyme in serum correlated with its ability to enhance growth performance in juvenile fish. Finally, the PACAP mRNA expression and PACAP immunoreactivity detected in peripheral blood leucocytes from juvenile catfish suggest a direct autocrine or/and paracrine mechanism of regulation of this peptide to mediate immune functions in fish.
迄今为止，已发表的关于 PACAP 在鱼类中的作用的体内研究较少，这些研究涉及繁殖、大脑发育和摄食行为。最近，我们首次证明，除了其神经内分泌作用外，PACAP 还影响鱼类幼虫的免疫功能。在这项工作中，我们评估了腹腔注射重组 Clarias gariepinus PACAP 对幼鱼重要免疫参数的影响。我们观察到，单次注射重组肽（0.1μg/克体重）能够在给药 24 小时后分别增加幼年鲶鱼 C. gariepinus 和罗非鱼 Orechromis niloticus 血清中的一氧化氮合酶衍生代谢物（NOS）和总免疫球蛋白 M（IgM）浓度。此外，我们的结果表明，重组 PACAP 增加了血清中的 IgM、NOS 和溶菌酶，这与其增强幼鱼生长性能的能力相关。最后，从幼年鲶鱼外周血白细胞中检测到的 PACAP mRNA 表达和 PACAP 免疫反应性表明，这种肽介导鱼类免疫功能的调节具有直接的自分泌或/和旁分泌机制。
