华鲮鳃表面形态结构扫描电镜观察

应用扫描电镜对华鲮Sinilabeor rendahli鳃耙、鳃弓、鳃丝和鳃小片的形态结构进行了观察.鳃耙和鳃弓表面凹凸不平,分布着大量丘突.鳃丝和鳃耙表面有大量粘液细胞分布,鳃丝上皮细胞表面密布微嵴,氯细胞附着在鳃丝表面和鳃小片侧表面.鳃小片薄、表面凹凸不平,垂直排列在鳃丝上.鳃丝和鳃小片的表面形态结构特征有助于提高鱼鳃的气体交换效率.     

珠江口池养梭鱼鳃的光镜、扫描和透射电镜观察

应用光学显微镜、扫描电镜和透射电镜对珠江口池塘养殖梭鱼Liza haematocheila鳃的组织结构、表面形态特征及鳃小片超微结构进行了观察。结果表明梭鱼具有4对鳃,每个鳃由鳃弓、鳃丝、鳃小片和鳃耙组成。梭鱼鳃丝和鳃小片的表面结构和超微结构与其他硬骨鱼类的基本相似,鳃丝表面分布有众多规则或不规则的环形微嵴、沟、坑、孔等结构。鳃丝分为呼吸区和非呼吸区,呼吸区较为平滑,上皮细胞表面无微嵴,呈皱褶状;非呼吸区分布有沟、坑、孔等结构,上皮细胞有较规则的指纹状微嵴。鳃小片是最主要的呼吸场所,由基膜、上皮细胞、内皮细胞、柱细胞和毛细血管网组成。泌氯细胞主要分布在鳃小片基部,并有开口通往外界。本文还探讨了梭鱼鳃的结构与其功能的密切关系。     

不同盐度下鲻鱼幼鱼鳃和肾组织结构变化

采用组织切片技术,研究了不同盐度下鲻鱼幼鱼鳃和肾的显微结构变化,探讨这些变化与渗透压调节的关系.结果显示,随着盐度升高,鳃小片逐渐变窄,间距变小,鳃丝和鳃小片上泌氯细胞数量增多,体积变大.泌氯细胞集中分布在鳃小片基部,且向两侧扩布.高盐度组的S₄₀组,鳃小片上皮出现分离脱落现象.随着盐度梯度的升高,肾小球及各级肾小管的结构上出现了不同程度的萎缩现象.     

黄斑篮子鱼和金钱鱼鳃的扫描电镜观察

对两种鲈形目鱼类黄斑篮子鱼(Siganus oramin)和金钱鱼(Scatophagus argus)的鳃结构进行扫描电镜观察。结果表明,黄斑篮子鱼和金钱鱼鳃的表面结构及微细结构与其他硬骨鱼类基本相似,鳃丝表面都具有规则或不规则分布的环形微嵴、沟、坑、孔等结构。黄斑篮子鱼的鳃片中部鳃丝表皮有大量凸起,而端部鳃丝表皮的凹凸程度明显较低,黄斑篮子鱼的鳃小片高度较金钱鱼鳃小片高。黄斑篮子鱼和金钱鱼鳃上皮的扁平上皮细胞、氯细胞和黏液细胞的形态结构及数量分布存在细微的差异。黄斑篮子鱼鳃片鳃丝的端部和中部表面有黏液细胞,金钱鱼鳃丝表面的黏液细胞很难观察到,与大多数淡水鱼类相似。黄斑篮子鱼鳃丝表面分布的氯细胞数量多于金钱鱼,这可能与两种鱼生活环境、生活习性的长期演变相关。     

波纹唇鱼鳃丝的光镜、扫描和透射电镜观察

应用光学显微镜、扫描电镜和透射电镜对波纹唇鱼(Cheilinus undulatus)鳃的组织结构、表面形态特征及鳃小片超微结构进行了观察.结果表明,波纹唇鱼有3对全鳃,1对半鳃和1对伪鳃,鳃丝呈梳状紧密排列在鳃弓上,鳃小片紧密地镶嵌排列在鳃丝两侧,入鳃动脉、出鳃动脉和鳃小片毛细血管网组成鳃的血液系统.鳃丝非呼吸区分布...     

鲑点石斑鱼和大眼鳜鳃的扫描电镜观察

对鲈形目科、底栖生活、凶猛肉食性的鲑点石斑鱼 (Epinephelusfario)和大眼鳜 (Sinipercakneri)鳃的结构进行扫描电镜观察。结果表明 ,两种鱼鳃的表面结构和微细结构与其他硬骨鱼类基本相似 ,鳃丝表面都具有规则或不规则分布的环形微嵴、沟、坑、孔等结构 ;然而两者的鳃小片都较高 ,表面更加凹凸不平 ,是对低溶氧环境的适应。鲑点石斑鱼的鳃丝表面一部分较为平坦 ,另一部分则凹凸不平 ,其鳃小片高度也高于大眼鳜 ,因而具有更大的表面积和较高的摄氧效率。在扫描电镜下能在鲑点石斑鱼和大眼鳜的鳃上分辨出扁平上皮细胞、氯细胞和粘液细胞 3种细胞 :前者鳃上的扁平上皮细胞界限清楚 ,而后者的界限模糊且表面遍布不规则的微嵴 ;前者的鳃丝和鳃小片上氯细胞的数量明显多于后者 ,两者细胞形态也存在差异 ;而鳃丝表面的粘液细胞的数量则是后者较多。两种鱼鳃上的细胞的形态结构及数量分布存在的差异 ,可能与前者生活于海水而后者生活于淡水的不同生活环境有关。     

久效磷对美国红鱼鳃Na^＋／K^＋-ATP酶活性和超显微结构的影响

经不同试验浓度的久效磷(0．25、0．5、1．0和2．0mg·L^-1)处理美国红鱼4d后,分别对鱼鳃Na^+／K^+—ATP酶活性和氯细胞密度进行了测定和计数,并观察了鱼鳃组织显微结构和超微结构的变化。结果表明,低浓度久效磷(0．25mg·L^-1)处理可以诱导鱼鳃氯细胞大量增生,Na^+／K^+—ATP酶活性增强,随着试验浓度的增加,久效磷对鳃组织的损伤越来越重,Na^+／K^+—ATP酶活性逐渐降低;久效磷对鱼鳃显微结构的损伤表现为鳃小片上皮细胞水肿、脱离。鳃小片基部粘连。鳃小片上皮细胞角质化;超微结构变化主要为内质网、线粒体、微小管和核膜的水肿及部分溶解,这种损伤表现为由细胞膜到细胞核的动态过程。     

不同NaHCO3碱度对瓦氏雅罗鱼鳃组织结构的影响

研究采用组织学方法观察和比较了达里诺尔湖瓦氏雅罗鱼(Leuciscus waleckii, 碱水种)和松花江瓦氏雅罗鱼(淡水种)在相同碳酸盐碱度胁迫下(C_A0、C_A30和C_A50)鳃组织结构的差异, 探究瓦氏雅罗鱼碱水种耐高碱特性与鳃组织结构微观调整的适应性关系。结果显示, 随着碱度增加, 碱水种鳃丝变宽、鳃小片变长、鳃小片间距变大(P<0.05); 淡水种鳃丝变宽、鳃小片间距变大(P<0.05), 鳃小片长度在C_A30时显著变长(P<0.05), 而在C_A50时与对照组无明显差异(P>0.05)。碱水种在C_A30和C_A50的氯细胞数量与对照组相比明显增加, C_A50的氯细胞排列更加紧密并且有叠加现象, 扁平上皮细胞变大, 细胞表面增厚; 淡水种在C_A30时的氯细胞数量明显多于C_A50, 但在碱度胁迫下, 鳃小片出现破损, 扁平上皮细胞、柱细胞和血细胞融合、脱落现象严重。另外, 在碱水种和淡水种鳃耙上皮细胞中发现了大量黏液细胞分泌, 随着碱度增加, 黏液细胞由大而稀疏变为小而密集, 其中碱水种的黏液细胞数量较淡水种多, 而且排列更为整齐、密集。鳃组织学研究结果表明, 瓦氏雅罗鱼碱水种通过保持鳃组织结构和生理功能的完整性达到对高碱环境的长期适应, 而淡水种则因鳃细胞融合、脱落造成生理功能丧失, 不能长期适应高碱环境。研究结果可为淡水鱼类在盐碱水的移植驯化提供依据和指导。     

盐度对大麻哈鱼幼鱼存活率、鳃ATP酶活力及其组织结构的影响

为研究不同盐度对大麻哈鱼幼鱼存活率、鳃ATP酶活力及其组织结构的影响, 试验共设置4个盐度组(S0、S8、S16、S24), 试验周期42d, 解剖取鱼鳃测定ATP酶活力, 并运用组织切片及扫描电镜技术观察其鳃组织结构的变化。结果显示: S8和S16组大麻哈鱼幼鱼存活率最高, 均达到98.89%, S0组存活率为94.45%, 而S24组存活率最低, 为83.34%。随着盐度的升高, 大麻哈鱼幼鱼鳃组织Na+/K+-ATP和Ca2+/Mg2+-ATP酶活力均呈现出先升高后下降的趋势且酶活力最高的均为S8组、最低的为S24组。鳃丝宽度随盐度升高逐渐增大且各组之间呈现出显著性差异(P<0.05), 而鳃小片长度和宽度均随盐度升高逐渐减小。扫描电镜结果表明随着盐度的升高线粒体丰富细胞数量逐渐增多、顶膜变小且微绒毛消失; 同S0组相比, S8组和S16组鳃丝表面扁平上皮细胞之间的轮廓更加清楚且环形微脊条纹清晰, 而S24组鳃丝表面扁平上皮细胞之间界限模糊, 环形微脊间有融合或间断情况; 鳃小片底部扁平上皮细胞表层结构由清晰逐渐变得混乱、气孔数量逐渐减少且孔径变小。因此推测大麻哈鱼幼鱼在降海阶段适宜的盐度生存范围可能介于8‰—16‰, 具体有待进一步研究。     

遮目鱼幼鱼鳃线粒体丰富细胞的形态结构及其在不同盐度下的变化

该实验通过普通光学显微镜、透射电子显微镜和扫描电子显微镜的方法,研究不同盐度条件下(盐度0、10、20、27、35)广盐性海水鱼类遮目鱼(Chanos chanos)幼鱼鳃器官结构和鳃上线粒体丰富细胞分布及结构的变化。鳃线粒体丰富细胞呈椭圆形或卵圆形,内含有大量线粒体,细胞核较大。在不同盐度条件下,遮目鱼幼鱼出现两种鳃线粒体丰富细胞:一种是具有顶端小窝、线粒体体积较大的A型线粒体丰富细胞;另一种是单独存在、线粒体体积较小的B型线粒体丰富细胞。随着盐度降低,A型线粒体丰富细胞及其线粒体数量减少、体积减小,电子密度降低,顶端开口变小甚至关闭。盐度降至淡水条件下,鳃小片肿胀、脱落,鳃小片上增生出具有大面积平滑或波状的顶端开口的B型线粒体丰富细胞。结果表明,在高渗环境下,A型线粒体丰富细胞较为丰富和发达,其结构特征适应了离子分泌的功能,为海水型线粒体丰富细胞;在低渗环境下,B型线粒体丰富细胞较为丰富,其结构特征适应了离子吸收的功能,为淡水型线粒体丰富细胞。不同结构类型鳃线粒体丰富细胞的存在使得广盐性海水鱼类可以适应较广的盐度范围变化。     

Die Vaskularisation der Kiemen von Myxine glutinosa L. (Cyclostomata)

The angioarchitecture of the gills in Myxine glutinosa L. was studied by scanning electron microscopy of vascular corrosion casts (methylmethacrylate). It was found that the afferent branchial artery may be connected to the sinus peribranchialis by a papilla. The sinus is connected to delicate vessels and sinuses, which are interposed between meridionally arranged radial arteries. These delicate vascular formations continue into the interior of the gill and form a plexus on both poles of the gill folds. Light and scanning electron microscopical studies on the vascular endothelium of the afferent vessels of the gill lamellae reveal rounded endothelial cells, which are characterized by a high content of granula, by long cellular processes and by bridge-formations towards neighbouring cells. Supporting columns within the vascular system of the lamellae were found to be set up by several spirally arranged cells. SEM observations reveal goblet cells and numerous superficial epithelial cells with various numbers of microvilli and microridges forming the epithelial surface of the gill folds.     

鲻鱼嗅囊组织形态结构观察及功能探讨

实验用鱼为全长35.5~40.0 cm的野生鲻(Mugil cephalus),采用石蜡切片以及透射电镜技术对鲻的嗅囊以及嗅板细胞进行观察。结果表明:鲻的嗅觉器官由左右两个呈扁平椭球形嗅囊构成,分别由前后两个鼻孔与外界相通。嗅囊长径与眼径之比为0.80,长径与短径之比为2.09。嗅囊的嗅轴左右两边分别有垂直于嗅轴并向上倾斜排列整齐的18~25个披针形嗅板,只有初级嗅板未见次级嗅板。嗅板由中央髓和两侧的嗅上皮两部分构成,中央髓由疏松的结缔组织和毛细血管组成。嗅上皮又分为感觉区和非感觉区,感觉区位于嗅板的内侧,具有发达纤毛,呈连续分布状态,非感觉区位于嗅板边缘,细胞纤毛较少。通过光镜和电镜的综合研究结果显示嗅上皮细胞大致可分为5类:基细胞、支持细胞、纤毛非感觉细胞、纤毛感觉细胞和柱状细胞。文章讨论了鲻的感官活动类型。     

合浦珠母贝鳃的显微与超微结构

合浦珠母贝(Pinctada fucata)是典型的滤食性瓣鳃类动物,也是我国重要的海水珍珠养殖贝类。本研究用光学显微镜、扫描电镜和透射电镜观察了合浦珠母贝鳃的显微和超微结构。结果表明,合浦珠母贝鳃结构属于异丝鳃型,左右两侧各2个鳃瓣,每个鳃瓣由内鳃瓣和外鳃瓣组成。鳃瓣由主鳃丝和普通鳃丝构成,主鳃丝在鳃瓣中主要起支架作用,每2根主鳃丝之间的9～12根普通鳃丝由"簇内连接"(intrabunchial junction)相连成簇。普通鳃丝之间通过"丝间连接"(interfilament junction)相连,丝间连接的上皮细胞与普通鳃丝的扁平细胞结构一样,为鳃的呼吸上皮。丝间连接的存在扩大了鳃的表面积,这种结构有助于进行气体交换。主鳃丝和普通鳃丝表面有前纤毛和侧纤毛,与食物运送和气体交换有关。普通鳃丝表面的纤毛为典型的"9+2"型微管结构。     

Presence of chloride cells in gill filaments and lamellae of the skate Torpedo marmorata

The morphology of chloride cells in the gill of the skate Torpedo marmorata is described from a light and an electron microscopic study. Chloride cells have been regularly observed in both the gill filament (or primary epithelium) and the lamellae (or secondary epithelium). Chloride cells located in the filament usually display convex apical regions with microvilli protruding amongst microridges of neighbouring pavement cells, whereas chloride cells in the lamellae are located between the two epithelial layers, and contact with the external milieu is via a narrow apical opening. Present observations are discussed in relation to data on the presence of chloride cells in the lamellae of marine teleost fish, and it is suggested that the occurrence of chloride cells all along the lamellae might be in some way inversely related to fish activity.     

Scanning electron microscopy of the respiratory surfaces of Saccobranchus (=Heteropneustes) fossilis (Bloch)

Summary The gill secondary lamellae are generally covered with epithelial cells whose outer surfaces form numerous microvilli. The surface of the primary lamellae is characterised by microridges. A particular type of surface sculpturing seems to be associated with given cell boundaries.Further evidence for the derivation of the air tube and fans which guard its entrance by modification of the basic gill structure has been obtained from both the gross surface architecture and microstructure of the individual cell surfaces. Secondary lamellae are represented by stubby projections which generally have a biserial arrangement. The outer surfaces of the epithelia overlying the capillaries of these respiratory islets are coated with microvilli as in the secondary lamellae. On the other hand, the relatively smooth-surfaced lanes between groups of respiratory islets have a microridged surface similar to that of the primary gill lamellae.It is suggested that previous estimates of surface area, and consequently diffusing capacities of the air-breathing organ, have been low in view of the increased surface, due to both their gross and microstructure. Estimates for gill surface area may need very little correction as the spaces between the microvilli and microridges are probably filled with mucus under normal conditions.We thank Mr. John Clements for his excellent technical assistance and the Department of Botany, Bristol University for the use of their scanning electron microscope     

A morphological study on posterior gills of the mangrove crab Ucides cordatus

Morphological and histological studies on posterior gills of the mangrove crab Ucides cordatus showed that the 5th gill (of 7) has a larger surface area and a greater number of lamellae compared to the 6th gill. Regular separation of gill lamellae, important when the gill is in air, is maintained by enlargements of the marginal canals. Conical, spine-like structures along the efferent vessel of both 5th and 6th gills were also observed. In addition, pillar cells, a discontinuous lamellar septum and a hypobranchial artery were observed. The presence of valve-like structures near the efferent vessel was also indicated. These structures, together with the pillar cells, may have a role in directing the hemolymph flow towards certain gills during particular physiological states. Localization of osmoregulatory epithelia in the lamellae of both gills was inferred from dimethylaminostyrylethylpyridiniumiodine staining. Apparently gills 5 and 6 have osmoregulatory epithelial cell patches of similar area, corresponding to 43% and 38% of the total lamellae area, respectively. However, their localization is quite different. Gill number 5 osmoregulatory patches seem to be restricted to the afferent region of the lamella whereas in gill number 6, they are more dispersed over the entire lamella. These differences may be related to the particular functional characteristics of these gills.     

Electron microscopic studies of the gill epithelium of the amphibian teleost Periophthalmus vulgaris]

The gill epithelium of the airdwelling fish Periophthalmus vulgaris has been studied with the electron microscope. The following celltypes can be distinguished: flat covering epithelial cells, chloride cells, mucous cells, basal cells, various leucocytes as well as a specific granule containing cell which is possibly an epithelial cell. The covering epithelial cells exhibit a relatively smooth apical surface and contain in their apical half densely packed microfilaments, pinocytotic vesicles are rare. These characteristics are not to be found in water dwelling fish and possibly represent adaptations to the air containing surroundings. In the chloride cells are numerous, especially in the basal halves of the secondary lamellae. The distal parts of the secondary lamellae the barrier for the respiratory gases measures about 0,9 micrometer. The basal cells are ribosome rich replacement cells. Two types of mucous cells occur. Individual intraepithelial nerve fibres have been observed.     

Surface ultrastructure of the olfactory rosette of an air-breathing catfish,Heteropneustes fossilis (Bloch)

The surface architecture of the olfactory rosette ofHeteropneustes fossilis (Bloch) has been studied by scanning electron microscopy. The olfactory rosette is an oval structure composed of a number of lamellae arranged pinnately on a median raphe. The raphe is invested with epithelial cells and pits which represent goblet cell openings. On the basis of cellular characteristics and their distribution the lateral surface of each olfactory lamella is identified as sensory, ciliated non-sensory and non-ciliated non-sensory epithelium. The sensory epithelium is provided with receptor and supporting cells. The ciliated non-sensory epithelium is covered with dense cilia obscuring the presence of other cell types. The non-ciliated non-sensory epithelium is with many polygonal areas containing cells.     

Scanning electron microscopy of the gills of a freshwater catfish,Rita Rita

Variations in the gross morphology and surface architecture of the gill filaments and secondary lamellae of a freshwater catfish (Rita rita) have been investigated using scanning electron microscopy. Heterogeneity of the gill has been correlated with the distribution of lamellar water-flow at different regions of a gill filament. Higher lamellar water flow (cc/pore/cmH₂O/sec) was estimated for the middle region of the filaments. The filaments are covered with epithelial cells whose surface is provided with well-developed microridges. The lamellae are generally covered with microvillous epithelial cells. The variations in surface architecture of the gill filaments and secondary lamellae have been correlated with their probable functions.