Premium
Early axon and dendritic outgrowth of spinal accessory motor neurons studied with dii in fixed tissues
Author(s) -
Snider William D.,
Palavali Vivekanand
Publication year - 1990
Publication title -
journal of comparative neurology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.855
H-Index - 209
eISSN - 1096-9861
pISSN - 0021-9967
DOI - 10.1002/cne.902970206
Subject(s) - biology , spinal cord , anatomy , axon , growth cone , motor neuron , neuroepithelial cell , commissure , neuroscience , ventral nerve cord , process (computing) , embryonic stem cell , central nervous system , computer science , operating system , biochemistry , gene
We have utilized lateral diffusion of DiI in fixed tissues (Godement et al., '87: Development 101 : 697–713) to study early axon and dendritic outgrowth of spinal accessory motor neurons in embryonic rats. Crystals were placed in the central canal of the cervical spinal cord near the ventral commissure in order to label growing accessory axons anterogradely and on the spinal accessory nerve to label somata and dendrites retrogradely. Animals were studied on E11–E13. We show here that it is possible to stain axonal and dendritic processes from the earliest stages of motor neuron differentiation by using DiI. Our results demonstrate that, unlike axons of other cervical motor neurons, accessory axons traverse the lateral region of the embryonic cord, which consists of neuroepithelial endfeet. Thus an affinity for neuroepithelial endfeet could partially explain their unusual intraspinal trajectory. We also show that morphology of the spinal accessory growth cones differs according to position along the accessory nerve pathway. Finally, we show that accessory motor neuron axons are in the region of their target precursors prior to the initiation of dendritic arborization. Use of DiI in fixed tissue allows study of process outgrowth in mammalian spinal cord with detail previously obtainable only in nonmammalian vertebrates.