Petrova V G
Arkh Anat Gistol Embriol. 1980 Aug;79(8):70-8.
As the investigation performed demonstrated, there is no principle differences in cytological organization in kidneys of five species of Amphibia whose mode of life to a certain extent is connected with water environment. Nevertheless, in different species epithelium of proximal parts of nephrons demonstrates various intensity of apocrinic secretion. Granules situating in the supranuclear zone of the epithelial cells of these parts are, in fact, autophagic lysosomes, their function is evidently connected with both lysis of the absorbed proteins and with autolysis of the apical cellular part in the process of secretion. The epithelial cytoplasm in the distal part of the nephron is characterized by a high succinate dehydrogenase activity; it is connected with its main function--osmoregulation. There are dark and light cells, resembling those in higher vertebrates, in the connecting part and in the collecting tubes. Ultrastructural organization of the brown frog nephron cells has much in common with that of epithelium of the secondary kidney urinary canaliculi.
正如所进行的研究所表明的，在生活方式在一定程度上与水环境相关的五种两栖动物的肾脏中，细胞学组织没有本质区别。然而，在不同物种中，肾单位近端部分的上皮细胞表现出不同强度的顶浆分泌。位于这些部分上皮细胞核上区的颗粒实际上是自噬溶酶体，它们的功能显然与吸收蛋白质的分解以及分泌过程中顶端细胞部分的自溶都有关。肾单位远端部分的上皮细胞质具有高琥珀酸脱氢酶活性；这与其主要功能——渗透调节有关。在连接部和集合管中有深色和浅色细胞，类似于高等脊椎动物中的细胞。棕蛙肾单位细胞的超微结构组织与次级肾泌尿小管上皮的超微结构组织有许多共同之处。
