We studied the opisthonephric (mesonephric) kidneys of adult male and female Xenopus laevis using scanning electron microscopy (SEM) of vascular corrosion casts and light microscopy of paraplast embedded tissue sections. Both techniques displayed glomeruli from ventral to mid‐dorsal regions of the kidneys with single glomeruli located dorsally close beneath the renal capsule. Glomeruli in general were fed by a single afferent arteriole and drained via a single thinner efferent arteriole into peritubular vessels. Light microscopy and SEM of vascular corrosion casts revealed sphincters at the origins of afferent arterioles, which arose closely, spaced from their parent renal arteries. The second source of renal blood supply via renal portal veins varied interindividually in branching patterns with vessels showing up to five branching orders before they became peritubular vessels. Main trunks and their first‐ and second‐order branches revealed clear longish endothelial cell nuclei imprint patterns oriented parallel to the vessels longitudinal axis, a pattern characteristic for arteries. Peritubular vessels had irregular contours and were never seen as clear cylindrical structures. They ran rather parallel, anastomosed with neighbors and changed into renal venules and veins, which finally emptied into the ventrally located posterior caval vein. A third source of blood supply of the peritubular vessels by straight terminal portions of renal arteries (vasa recta) was not found.

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成年蛙蛙的肾脏微血管系统，非洲爪蟾：血管腐蚀铸件的扫描电子显微镜研究

我们使用血管腐蚀模型的扫描电子显微镜 (SEM) 和 paraplast 嵌入组织切片的光学显微镜研究了成年雄性和雌性非洲爪蟾的前肾（中肾）肾脏。这两种技术都显示了从肾脏腹侧到中背侧区域的肾小球，单个肾小球位于肾被膜下方的背侧。肾小球通常由单个传入小动脉供血，并通过单个较细的传出小动脉排入管周血管。血管腐蚀铸件的光学显微镜和 SEM 显示传入小动脉起源处的括约肌，这些小动脉与它们的母肾动脉间隔很近。通过肾门静脉的肾脏血液供应的第二个来源在分支模式上各不相同，血管在成为管周血管之前显示出多达五个分支顺序。主干及其一级和二级分支显示出清晰的长内皮细胞核印迹图案，方向平行于血管纵轴，这是动脉的特征图案。管周血管具有不规则的轮廓，从未被视为清晰的圆柱形结构。它们相当平行，与邻居吻合并变成肾小静脉和静脉，最终汇入位于腹侧的后腔静脉。未发现肾动脉直末端部分（直肠血管）管周血管的第三个血液供应来源。主干及其一级和二级分支显示出清晰的长内皮细胞核印迹图案，方向平行于血管纵轴，这是动脉的特征图案。管周血管具有不规则的轮廓，从未被视为清晰的圆柱形结构。它们相当平行，与邻居吻合并变成肾小静脉和静脉，最终汇入位于腹侧的后腔静脉。未发现肾动脉直末端部分（直肠血管）管周血管的第三个血液供应来源。主干及其一级和二级分支显示出清晰的长内皮细胞核印迹图案，方向平行于血管纵轴，这是动脉的特征图案。管周血管具有不规则的轮廓，从未被视为清晰的圆柱形结构。它们相当平行，与邻居吻合并变成肾小静脉和静脉，最终汇入位于腹侧的后腔静脉。未发现肾动脉直末端部分（直肠血管）管周血管的第三个血液供应来源。管周血管具有不规则的轮廓，从未被视为清晰的圆柱形结构。它们相当平行，与邻居吻合并变成肾小静脉和静脉，最终汇入位于腹侧的后腔静脉。未发现肾动脉直末端部分（直肠血管）管周血管的第三个血液供应来源。管周血管具有不规则的轮廓，从未被视为清晰的圆柱形结构。它们相当平行，与邻居吻合并变成肾小静脉和静脉，最终汇入位于腹侧的后腔静脉。未发现肾动脉直末端部分（直肠血管）管周血管的第三个血液供应来源。