Effect Of Neuropeptide S On The Secretion Of Cytokines In Muscovy Serum And Immune Organs

Neuropeptide S was one novel kind of 20 amino acids neuropeptide that was found by Sato S, et al in 2002 used reverse pharmacology method. Because of all the N-terminal amino acid residues in all reported species were serine, it was named neuropeptide S.All the reported functions of NPS was conducted by the combination with its receptor, both of which can form a new NPS-NPSR system.The widely distribution or expression of NPS and NPSR in animals may indicate that they can be involved in the regulation of a variety of important physiological functions, such as wake, stress, food, learning and memory, and immune function and so on. But these studies have reported merely focused on human, pigs, rabbits and mice, so, the effect of NPS on the immune system in poultry has not been reported. Therefore, we use the gene clone, pathological section, semi-quantitative RT-PCR, ELISA and so on to research the gene sequence of NPS Muscovy ducks, further explore its immunomodulatory effects on duck and development it as immune enhancer provides some theoretical basis.(Purpose)To obtain the gene sequence of Muscovy ducks neuropeptide S gene cloning, and further explore the effect of NPS on the infected H9N2 Muscovy ducks serum cytokine and immune organs effect. (Method) In this paper,we using gene cloning techniques clone Muscovy ducks NPS gene.175 Muscovy ducks were randomly divided into five groups:the control group A, NPS control group B, injection virus group C, first injection of the virus and then injected of NPS Group D, first injection of NPS and then injected the virus group E. On the feeding 28 days, we observed Muscovy ducks injected virus generally lesions. Blood, serawere collected and anaysis the changes of secretion cytokines in serum; then, we dissected Muscovy ducks, put their thymus, spleen, bursal and other immune organs in 10% formalin. All the sample were fixed by 10% formalin and embedded by Paraffin,Sliced, HE staining and histological lesions. The expression of cytokines in serum or in immune organs was detected by ELISA or Real-timeqRT-PCR. The results were shown as following,(1)The Muscovy ducks NPS cDNA sequence was shown in 181 bp, after the DNAstar analysis, NPS genes showed highly homologous between different species, Muscovy ducks and chickens NPS is highly close to each other..(2)Most yolk sac enlargement, tracheal mucosal edema congestion, slight enlargement of the liver, ducks thymus larger than normal and have diffuse bleeding were found after necropsy injection of H9N2. Endoscopic injection of the virus ducks can be observed Muscovy thymus, spleen showed different degrees of lesions.(3) The effect of injections with NPS on the secretion of cytokines in Muscovy ducks serum and immune organs. In the serum, first injection NPS and then injected with the virus were shown in best; in the immune organs, the highest expression of cytokines was in NPS control group, but first injections of NPS and then injected the virus better than the first injection of the virus and then injected with NPS in the experimental group.In conclusion, the ontained Muscovy NPS nucleotide and amino acid sequence showned highly homology between differnent related speciee. Intramuscular injection of NPS, can be appropriate to reduce pathologic changes of infection with the H9N2 avian influenza virus of Muscovy duck; and the secretion of cytokines were increased in Muscovy duck serum and the expression of cytokines mRNA in Muscovy duck bursal, spleen and other immune organs were increased relatively. These studies showed that NPS may be involved in the immunomodulatory effects of Muscoy duck.