Zamorska L
Folia Histochem Cytochem (Krakow). 1976;14(4):263-73.
The activity of some intracellular oxidative enzymes was studied histochemically in the cells of the thyroid follicles of teleost fishes of the genus Xiphophorus. The experimental material consisted of animals of the red swordtail and Mexican swordtail breeds of Xiphophorus helleri and of melanotic Xiphophorus maculatus fishes. Observations were carried out on adult specimens of both sexes, including pregnant femals of Mexican swordtail. Moreover, immature Mexican swordtails of both sexes were examined. Thyroid follicles were found to be present in the subpharyngeal region of all fishes studied. The distribution of these follicles as well as their number and form depended on sex, age and on the analysed stage of prenancy. A smaller number and size of thyroid follicles were characteristic of immature specimens, whereas they were most numerous in the thyroids of pregnant fishes. The follicles were arranged in characteristic dense aggregations, especially in the melanotic platyfish. The follicular eipthelium in the fishes under study was usually cubical, but pregnant and non-pregnant adult females also contained a considerable number of larger follicles with flattened epithelium. Besides, thyroid follicles of multilayer epithelium were rather frequently encountered, especially in male fishes, irrespective of their age. The thyroid follicle cells of these fishes demonstrated invariably high activities of reduced NAD and NADP dehydrogenases and of beta-hydroxybutyrate dehydrogenase, and a low activity of succinat dehydrogenase. The intensities of alpha-glycerophosphate and lactate dehydrogenases and of cytochrome oxidase varied with sex, age and breed of the studied fishes. The immature and pregnant fishes showed the most clearly pronounced differences in the intensity of enzymic activity, the thyroid follicles of immature specimens revealing a high activity of lactate dehydrogenase and low activity of cytochrome oxidase, an inverse picture being seen in pregnant fishes. The adult forms of both sexes exhibited an enhanced activity of cytochrome oxidase and a decline in that of lactate dehydrogenase. The observed differences in the intensities of enzymic acitivities in the thyroids of the studied fishes are related with functions of this gland which in the period of growth are different from those in the period of sexual maturity, and certainly also with individual metabolic characteristics of the studied fishes.
对剑尾鱼属硬骨鱼类甲状腺滤泡细胞中的一些细胞内氧化酶活性进行了组织化学研究。实验材料包括赫氏剑尾鱼的红剑尾和墨西哥剑尾品种的动物以及黑剑尾鱼。对两性成年标本进行了观察，包括墨西哥剑尾的怀孕雌性。此外，还检查了两性未成熟的墨西哥剑尾鱼。在所研究的所有鱼类的咽下区域均发现有甲状腺滤泡。这些滤泡的分布以及它们的数量和形态取决于性别、年龄以及所分析的怀孕阶段。甲状腺滤泡数量较少且体积较小是未成熟标本的特征，而在怀孕鱼类的甲状腺中数量最多。滤泡排列成特征性的密集聚集，尤其是在黑剑尾鱼中。所研究鱼类的滤泡上皮通常为立方形，但怀孕和未怀孕的成年雌性也含有相当数量的较大滤泡，其上皮为扁平状。此外，多层上皮的甲状腺滤泡相当常见，尤其是在雄性鱼类中，与年龄无关。这些鱼类的甲状腺滤泡细胞始终显示出还原型NAD和NADP脱氢酶以及β-羟丁酸脱氢酶的高活性，而琥珀酸脱氢酶的活性较低。α-甘油磷酸脱氢酶、乳酸脱氢酶和细胞色素氧化酶的活性强度随所研究鱼类的性别、年龄和品种而变化。未成熟和怀孕的鱼类在酶活性强度上表现出最明显的差异，未成熟标本的甲状腺滤泡显示乳酸脱氢酶活性高而细胞色素氧化酶活性低，怀孕鱼类则呈现相反的情况。两性成年个体表现出细胞色素氧化酶活性增强而乳酸脱氢酶活性下降。在所研究鱼类甲状腺中观察到的酶活性强度差异与该腺体在生长时期与性成熟时期不同的功能有关，当然也与所研究鱼类的个体代谢特征有关。
