团头鲂外周血细胞的显微结构及细胞化学特征

采用常规瑞氏染色和细胞化学染色方法对团头鲂(Megalobrama amblycephala)外周血细胞的显微结构及细胞化学特征进行了观察。在团头鲂外周血细胞中可区分出六类细胞: 红细胞、淋巴细胞、单核细胞、嗜中性粒细胞、嗜酸性粒细胞和血栓细胞。其中淋巴细胞是除红细胞外含量最多的细胞, 其次分别为血栓细胞、单核细胞、嗜中性粒细胞、嗜酸性粒细胞。成熟红细胞多为卵圆形, 表面光滑, 胞核呈椭圆形或圆形, 染色质较为致密; 淋巴细胞多呈圆形, 胞质较少, 胞核常偏位; 单核细胞多为圆形, 胞核呈圆形或椭圆形, 胞质内可见空泡状结构; 嗜中性粒细胞近似圆形, 胞核常偏于细胞一侧, 呈分叶状、肾形或椭圆形, 核质界限清晰; 嗜酸性粒细胞一般为圆形, 胞核为肾形或椭圆形, 胞质中充满紫红色颗粒; 血栓细胞形态多样, 主要有椭圆形、纺锤形、长杆状和泪滴形, 核质比较大。淋巴细胞呈α-醋酸萘酚酯酶(ANAE)阳性, 呈过碘酸-雪夫(PAS)、氯乙酸AS-D萘酚酯酶(AS-DCE)弱阳性, 呈苏丹黑B(SBB)、酸性磷酸酶(ACP)、碱性磷酸酶(AKP)及过氧化物酶(POX)阴性; 单核细胞呈POX、ACP强阳性, PAS、SBB、AS-DCE和ANAE为阳性, 呈AKP阴性; 嗜中性粒细胞除PAS和ANAE为弱阳性外, 其他染色结果和单核细胞相同; 嗜酸性粒细胞呈POX、ANAE强阳性, SBB、ACP阳性, PAS及AS-DCE则为弱阳性, 呈AKP阴性; 血栓细胞呈PAS、AS-DCE及ANAE弱阳性, 呈SBB、ACP、AKP及POX阴性。团头鲂外周血细胞的显微结构及细胞化学特征与其他鱼类具有相似之处, 但亦有其明显的物种特异性。该研究结果可作为监测团头鲂健康状态的依据, 为其养殖及病理诊断提供基础资料。

MICROSCOPIC STRUCTURE AND CYTOCHEMICAL CHARACTERISTICS OF PERIPHERAL BLOOD CELLS IN MEGALOBRAMA AMBLYCEPHALA

The microscopic structure and cytochemical characteristics of peripheral blood cells in Megalobrama amblycephala were observed by routine Wright staining and cytochemical staining. Six types of cells were distinguished in the peripheral blood cells in Megalobrama amblycephala: erythrocytes, lymphocytes, monocytes, neutrophils, eosinophils and thrombocytes. The lymphocytes are the most abundant blood cells except erythrocytes, followed by thrombocytes, monocytes, neutrophils and eosinophils. The mature erythrocytes are mostly oval with smooth surface, oval or round nuclei whose chromatin is denser. The lymphocytes are usually round, with less cytoplasm, and the nucleus is usually eccentrically located. The monocytes are mostly round, the nucleus is round or oval, and vacuoles can be observed in the cytoplasm. Neutrophils are nearly round, and their nuclei are usually eccentrically located, lobed, kidney or oval shaped, with clear nucleoplasm boundaries. Eeosinophils are usually round, with reniform or oval nuclei, and the cytoplasm is filled with purple granules. Thrombocytes have various forms, most of which are oval, spindle, long-rod shaped or teardrop shaped, and their nucleo-cytoplasmic ratio is large. The lymphocytes were positive for periodic acid-Schiff reaction (PAS), weakly positive for naphythol AS-D chloroacetate esterase (AS-DCE) and α-naphthol ace-tate esterase (ANAE), and negative for Sudan black B (SBB), acid phosphatase (ACP), alkaline phosphatase (AKP) and peroxidase (POX). The monocytes were strongly positive for POX and ACP, while PAS, positive for SBB, AS-DCE and ANAE were and negative for AKP. Except weakly positive for PAS and ANAE, the cytochemical staining pattern of neutrophils were the same as those of monocytes. Eosinophils showed strong positive for POX and ANAE, positive for SBB and ACP, weak positive for PAS and AS-DCE, and negative for AKP. The thrombocytes were weakly posi-tive for PAS, AS-DCE and ANAE and negative for SBB, ACP, AKP and POX. The microstructural and cytochemical characteristics of peripheral blood cells in Megalobrama amblycephala were similar to those of other fishes, but also had obvious species specificity. The results of this investigation can be used as a basis for monitoring the health status of Megalobrama amblycephala and provide basic data for its farming and pathological diagnosis.