Fazan Valéria Paula Sassoli, Ma Xiuying, Chapleau Mark W, Barreira Amilton Antunes
Department of Surgery and Anatomy, School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, São Paulo, Brazil.
Anat Rec. 2002 Dec 1;268(4):399-404. doi: 10.1002/ar.10174.
The detailed morphology of the renal nerves in mice has not been reported previously. The aims of this study were to describe the general morphology of the extrinsic renal nerve in C57BL/6 mice, and determine its morphometric parameters. The major renal nerve innervating the left kidney was isolated in five mice. Thin sections of the nerve segments were then examined by transmission electron microscopy. The renal nerve averaged 35.4 +/- 3.6 (S.E.M.) microm in diameter and 741 +/- 104 microm in area. The renal nerve contained an average of 830 +/- 169 unmyelinated fibers and only 4.6 +/- 1.7 myelinated fibers. The axon diameter of myelinated and unmyelinated fibers averaged 2.2 +/- 0.3 microm and 0.76 +/- 0.02 microm, respectively. The diameter of the unmyelinated fibers ranged from 0.3 to 2.0 microm, and the distribution histogram was unimodal. The majority of fibers (85%) had diameters of 0.6-1.0 microm. These results are similar to those obtained for renal nerves of rats with respect to the predominance of unmyelinated fibers. However, the diameter of unmyelinated fibers is larger in rats and the distribution histogram of rat unmyelinated fibers is bimodal, in contrast to the unimodal distribution in mice. The morphological description of the renal nerves in mice provides baseline data for further investigations of the structural basis of altered autonomic reflexes. The results will be useful in analyses of genes that influence the development and structure of sympathetic and sensory innervation of the kidney in genetically manipulated mice.
此前尚未有关于小鼠肾神经详细形态学的报道。本研究的目的是描述C57BL/6小鼠肾外神经的一般形态，并确定其形态学参数。在五只小鼠中分离出支配左肾的主要肾神经。然后通过透射电子显微镜检查神经节段的薄切片。肾神经平均直径为35.4±3.6（标准误）微米，面积为741±104微米。肾神经平均含有830±169条无髓纤维和仅4.6±1.7条有髓纤维。有髓和无髓纤维的轴突直径分别平均为2.2±0.3微米和0.76±0.02微米。无髓纤维的直径范围为0.3至2.0微米，分布直方图为单峰。大多数纤维（85%）的直径为0.6 - 1.0微米。就无髓纤维占优势而言，这些结果与大鼠肾神经的结果相似。然而，大鼠无髓纤维的直径更大，且大鼠无髓纤维的分布直方图为双峰，与小鼠的单峰分布形成对比。小鼠肾神经的形态学描述为进一步研究自主反射改变的结构基础提供了基线数据。这些结果将有助于分析在基因操作小鼠中影响肾交感和感觉神经支配发育及结构的基因。
