肉鸡组织脏器的急性热应激损伤及HSP_(90)的表达

Tissue damages of heat-stressed broilers and expression of HSP_(90)

将 30日龄AA肉鸡在 ( 4 0± 1)℃高温中分别持续 2、 3、 5和 10h ,定期剖杀 ,进行临床血液病理学、组织病理学和免疫组织化学检测。结果表明 :在热应激 2～ 5h内 ,受试鸡外周血液中肌酸激酶活性持续升高 (P <0 0 1) ;当热应激持续到 10h时其活性出现降低 ,但仍明显高于对照组 (P <0 0 1)。受试鸡的组织脏器在应激前期损伤较严重 ,热应激 2～ 5h内 ,各主要脏器组织如心肌纤维、肝细胞、肾小管上皮细胞出现颗粒变性和脂肪变性 ,甚至坏死 ;而后期组织细胞的损伤则无明显坏死。提示在热应激持续一定时间后 ,机体可通过自身调节逐渐获得对高热的耐受能力。免疫组化结果显示 ,HSP90 广泛分布在热应激受试鸡脏器组织细胞的胞浆和胞核中 ,尤其在组织的小动脉、毛细血管内皮细胞内呈现强表达。提示血管壁中HSP90 可能通过血管的舒缩而影响组织器官的血液供应。

One hundred AA broilers were divided into 5 groups at random and 20 broilers per group.After 30 days adaptive feeding under the normal temperature,80 broilers were suddenly stressed by increasing environment temperature from(22±1)℃ to (40± 1)℃.Clinical blood parameter,histopathology and immunohistochemistry of timely killed heat stressed chickens were demonstrated at 2 h,3 h,5 h and 10 h respectively.The activity of creatine kinase(CK)which implies myocardium damage increased significently from 2 h to 5 h( P < 0 01)and decreased at 10 h.All detected liver,kidney,heart of heat stressed chickens showed obvious degeneration,especially at 25 h heat stress period.HSP 90 widely distributed in the cytoplasm and nuclei in detected tissue cells.Strongly expressed HSP 90 was also detected in the endothelium and artery wall of all detected tissue organs.It is suspected to imply that there may be a relation between the vasoconstriction and the HSP 90 expression,which influence the blood flow regulation.