NO在雏鸡球虫感染过程中的作用

The Effect of NO During E.tenella or E.acervulina Infection of Broilers

研究以腹腔注射途径给予试验雏鸡cNOS抑制剂L NAME、L NA以及iNOS抑制剂L AG ,通过测定血浆NO-2 水平、肠道粘膜NOS活性、雏鸡日增重以及肠道病变计分、肠道组织切片中球虫数量、O .P .G值、异常粪便百分率等指标 ,研究了NO在雏鸡感染E .tenella或E .acervulina过程中的作用。试验结果表明 ,在雏鸡感染E .tenella或E .acervulina后 ,每日连续给予L AG或L NAME ,不但加重了雏鸡的肠道组织显微病变 ,而且使肠道组织切片中的球虫数量增多。此外L AG或L NAME处理还使感染雏鸡的O .P .G值和肠道病变记分等指标出现不同程度的升高 ,但与感染对照组的相比未见显著性影响。另外 ,无论是NO-2 测定结果 ,还是NOS活性测定结果均表明 ,3种NOS抑制剂对感染E .acervulina雏鸡体内NO的生成均有较好的抑制作用 ,其中以L AG的抑制作用最为理想 ,L AG处理组雏鸡血浆NO-2 水平或肠道粘膜NOS活性值均与给予的L AG剂量之间呈现较好的剂量依赖性递减关系。结果提示 ,在雏鸡感染球虫过程中 ,体内大量生成的NO对球虫具有一定的毒性作用。NO可能是在雏鸡E .tenella和E .acervulina感染过程中发挥作用的一种效应分子。

It is well identified that nitric oxide(NO),a labile and highly reactive radical,can be synthesized in most part of animal and human body.NO has been demonstrated to play different roles in organism.As a molecule of transmitter and effector,NO participates in the processes of microorganism infection.The effects of NO during E.tenella or E.acervulina infection processes using cNOS inhibitors such as L-NAME,L-NA,and iNOS inhibitor L-AG have been studied in this research.14-day-old Huangyu broilers were challenged with E.tenella at the dose of 2.0×10 4 oocysts per broiler or E.acervulina at the dose of 2.7×10 4 oocysts per broiler.The 14-day-old broilers received NOS inhibitors continuously for 7 days after the day of challenge.The experimental results showed that the plasma levels of NO - 2 and NOS activity of broilers in infective control groups were significantly higher than those of control one (P<0.05).The plasma levels of NO - 2 and NOS activity in broilers of each NOS inhibitors-treated group were decreased significantly than those in infective control one (P<0.05).These results indicated that L-NAME,L-NA,and L-AG might successfully inhibit the NO production in broilers.The clinical signs,gross and histologic lesions and coccidiosis of broilers in L-NAME-treated group and L-AG-treated group were exacerbated.The experimental results imply that NO which is produced during Eimeria infection processes has some toxic effect on Eimeria parasite,and some beneficial effect on broilers organism.Come to the conclusion,as an effector,NO play an important role in Eimeria infection of broilers.