Nitric oxide (NO) is gaseous bioactive molecule that is synthesized by NO synthase (NOS). Inducible NOS (iNOS) expression occurs in response to pathogenic challenges, resulting in the production of large amounts of NO. However, there is a lack of knowledge regarding neuronal NOS (nNOS) and endothelial NOS (eNOS) in birds during pathogenic challenge. Therefore, the present study was conducted to determine the influence of intraperitoneal (IP) injection of zymosan (cell wall component of yeast) and lipopolysaccharide (LPS, a cell wall component of gram-negative bacteria) on NOS expression in chicks (). Furthermore, the effect of NOS inhibitors on the corresponding behavioral and physiological parameters was investigated. Zymosan and LPS injections induced iNOS mRNA expression in several organs. Zymosan had no effect on eNOS mRNA expression in the organs investigated, whereas LPS increased its expression in the pancreas. Zymosan and LPS decreased nNOS mRNA expression in the lung, heart, kidney, and pancreas. The decreased nNOS mRNA expression in pancreas was probably associated with the NO from iNOS provided that such effect was reproduced by IP injection of sodium nitroprusside, which is a NO donor. Furthermore, pancreatic nNOS mRNA expression decreased following subcutaneous injection of corticosterone. Furthermore, IP injections of a nonspecific NOS inhibitor, NG-nitro-L-arginine methyl ester, and an nNOS-specific inhibitor, 7-nitroindazole, resulted in the significant decreases in food intake, cloacal temperature, and feed passage via the digestive tract in chicks. Collectively, the current findings imply the decreased nNOS expression because of fungal and bacterial infections, which affects food intake, body temperature, and the digestive function in birds.

中文翻译：

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酵母聚糖和脂多糖降低雏鸡外周器官神经元一氧化氮合酶的基因表达

一氧化氮（NO）是由一氧化氮合酶（NOS）合成的气态生物活性分子。诱导型一氧化氮合酶 (iNOS) 表达是为了应对病原体的挑战，从而产生大量的一氧化氮。然而，人们对病原体攻击期间鸟类的神经元一氧化氮合酶（nNOS）和内皮一氧化氮合酶（eNOS）缺乏了解。因此，本研究旨在确定腹腔（IP）注射酵母聚糖（酵母细胞壁成分）和脂多糖（LPS，革兰氏阴性菌细胞壁成分）对雏鸡NOS表达的影响。此外，还研究了 NOS 抑制剂对相应行为和生理参数的影响。酵母聚糖和 LPS 注射可诱导多个器官中 iNOS mRNA 的表达。酵母聚糖对所研究器官中的 eNOS mRNA 表达没有影响，而 LPS 则增加了胰腺中的 eNOS mRNA 表达。酵母聚糖和 LPS 降低了肺、心脏、肾和胰腺中 nNOS mRNA 的表达。胰腺中 nNOS mRNA 表达的降低可能与 iNOS 产生的 NO 有关，前提是通过腹腔注射硝普钠（NO 供体）来重现这种效应。此外，皮下注射皮质酮后，胰腺 nNOS mRNA 表达降低。此外，腹腔注射非特异性NOS抑制剂NG-硝基-L-精氨酸甲酯和nNOS特异性抑制剂7-硝基吲唑可显着降低食物摄入量、泄殖腔温度和消化道饲料通过率在小鸡身上。总的来说，目前的研究结果表明，由于真菌和细菌感染，nNOS 表达下降，这会影响鸟类的食物摄入、体温和消化功能。