Luff S E, Hengstberger S G, McLachlan E M, Anderson W P
Baker Medical Research Institute, Prahran, Victoria, Australia.
J Neurocytol. 1991 Oct;20(10):781-95. doi: 10.1007/BF01191730.
Ultrastructural analyses of serial thin sections have revealed two structurally different types of sympathetic axon innervating the afferent and efferent juxtaglomerular arterioles and the intralobular arteries in the outer cortex of the rabbit kidney. Both types of axon have also been found in association with an afferent arteriole in rat kidney. One axon type consists of relatively large diameter unmyelinated axons bearing varicosities in the form of slight expansions. The varicosities have a distinct structural zonation: synaptic vesicles occupy the expansion which faces the smooth muscle cells, whereas the rest of the axon is filled with numerous microtubules. The other axon type has varicosities containing vesicles and mitochondria but few microtubules. The varicosities are generally small and the intervaricosities very thin. The relationship of both axon types with support cells and/or basal lamina is sometimes poorly defined. Both axon types are catecholaminergic as their vesicles take up 6-hydroxydopamine and both types form junctions with arteriolar smooth muscle cells. As well as differing from each other, both types of intrarenal axon differ in several respects from those which innervate other arterial vessels.
对连续超薄切片的超微结构分析显示，有两种结构不同的交感神经轴突支配家兔肾脏外皮质的传入和传出球旁小动脉以及小叶间动脉。在大鼠肾脏的一条传入小动脉中也发现了这两种轴突。一种轴突类型由直径相对较大的无髓轴突组成，带有呈轻微膨大形式的曲张体。这些曲张体有明显的结构分区：突触小泡占据面向平滑肌细胞的膨大部分，而轴突的其余部分充满大量微管。另一种轴突类型的曲张体含有小泡和线粒体，但微管很少。曲张体通常较小，曲张体之间的部分很细。两种轴突类型与支持细胞和/或基膜的关系有时界定不清。两种轴突类型都是儿茶酚胺能的，因为它们的小泡摄取6-羟基多巴胺，并且两种类型都与小动脉平滑肌细胞形成连接。除了彼此不同之外，两种肾内轴突在几个方面也与支配其他动脉血管的轴突不同。
