溶藻弧菌胞外产物注射赤点石斑鱼后的组织病理学观察

在注射溶藻弧菌胞外产物(ECP)48 h后,石斑鱼Epinephelus akaara出现死亡,临床症状表现为:运动迟缓,体色变深,腹部膨大,腹腔有明显的积水,肝脏出血有花斑,肾脏和脾脏肿大。病理组织切片观察发现:肝细胞坏死,解体,界限模糊,细胞核变形、裂解甚至消失;肝脏出血,肝索中有红细胞浸润,有的红细胞变形甚至破裂;肾小管上皮细胞脱落、坏死;肠粘膜上皮细胞脱落、坏死,微绒毛不整齐,模糊不清,脱落;脾窦和脾索不清晰,分界不清,且在脾窦和脾索中分布着大量的、形态不规则的红细胞。此外,还发现在肝脏、脾脏、肾脏、肠壁肌层、心肌和鳃等组织中存在一种相同结构,该结构有平滑肌环绕,管腔内壁衬以扁平上皮细胞,管腔中含有一团染成紫红色的物质,经推断为小动脉透明样变性,而在正常的组织切片中,均无此结构。

Histopathology of Epinephelus akaara Injected with the Extracellular Products from Vibrio alginolyticus

The experimental fish injected intraperitioeally with the ECP from V.alginolyticus began to die after 48 h.The typical symptoms of ill fish were as follows: movement became sluggish,body color got dark,abdomen swelled and a great quantity of ascites could be observed in abdominal cavity;liver hemorrhagedwith lots of patches;kidney and spleen swelled,as well.The histopathological changes of spleen,kidney,intestine,myocardium,and gill tissues from dead or moribund Epinephelus spp.were observed.The results showed that the liver,spleen,kidney,intestine and myocardium presented a more or less pathological changes,especially great changes can be observed in the kidney and spleen.The results were described as follows: cells of liver were necrotic and deformative;the borderlines of cells were obscure;hemorrhage in liver and erythrocytes infiltrated in hepatic cords;the number of macrophages in liver increased;the spleen cells were necrotic with blurry structure,splenic arteriole expanding;epithelia of renal tubules underwent degeneration,necrosis and desquamation,even the whole epithelial layer desquamated;enteric epithelium cells were necrotic and desquamative and the microvilli were not clear.In addition,the identical structures that were observed in the liver,spleen,kidney,intestine,myocardium,but not found in the normal tissues were hyaline degeneration of arteriole.