de Ruiter A J
Cell Tissue Res. 1980;206(1):1-20. doi: 10.1007/BF00233603.
In sexually mature male sticklebacks, the renal tubular cells are transformed from ion reabsorbing to mucus secreting cells and in these fish concomitant changes take place in the glomeruli. The present study compares glomerular structure of immature males in fresh water (controls) to those of mature males in fresh water and to immature male sticklebacks in seawater. Glomerular structure is markedly altered in the latter two groups and the changes are similar to a large extent. In these two groups the renal capsules and glomeruli are smaller and the lumina of the glomerular capillaries decrease in diameter, while the number and size of the endothelial fenestrations are reduced. Mesangial cells proliferate and the mesangial matrix greatly expands in both the centrolobular region and the subendothelial space around the capillaries. The secretory activity of the podocytes is enhanced and is responsible for the observed increase in thickness of the outer layer of the basal lamina, the lamina rara externa. The area covered by the filtration slit membranes is reduced, probably as a consequence of fusion of the pedicels of the podocytes. The permeability characteristics of the glomerular filtration barrier for macromolecules, as studied with ferritin injections, remain unaltered. However, the observed differences point to a reduction of the glomerular filtration rate (GFR) during maturation in male sticklebacks, as well as during adaptation of sticklebacks to seawater. This conclusion is in line with physiological evidence.
在性成熟的雄性刺鱼中，肾小管细胞从离子重吸收细胞转变为黏液分泌细胞，并且在这些鱼中肾小球也发生了相应的变化。本研究比较了淡水环境中未成熟雄性刺鱼（对照组）、淡水环境中成熟雄性刺鱼以及海水中未成熟雄性刺鱼的肾小球结构。后两组的肾小球结构发生了显著改变，且在很大程度上相似。在这两组中，肾小囊和肾小球较小，肾小球毛细血管腔直径减小，而内皮窗孔的数量和大小减少。系膜细胞增殖，系膜基质在小叶中心区域和毛细血管周围的内皮下间隙均大幅扩张。足细胞的分泌活性增强，这导致观察到的基底膜外层即外疏松层厚度增加。滤过裂隙膜覆盖的面积减少，这可能是足细胞足突融合的结果。用铁蛋白注射研究发现，肾小球滤过屏障对大分子的通透性特征未发生改变。然而，观察到的差异表明，雄性刺鱼成熟过程中以及刺鱼适应海水过程中肾小球滤过率（GFR）降低。这一结论与生理学证据相符。
