Characterization of c-kit-positive neurons in the dorsal root ganglion of mouse.
Previously, we showed that c-kit receptor tyrosine kinase is expressed by a subpopulation of dorsal root ganglion (DRG) neurons, and that the ligand for the c-kit receptor, stem cell factor (SCF), induces the neurite outgrowth and supports the survival of these neurons in culture [16]. However, it is unknown which class of DRG neurons express c-kit receptor and which factor regulates differentiation and survival of c-kit-positive neurons. In the present study, we attempted to characterize c-kit positive neurons in the mouse DRG. The c-kit-positive neurons were small or medium in size, and 44% of these neurons contained substance P. Central fibers of the c-kit-positive neurons terminated in laminae I and II of the gray matter of the spinal cord. These results suggest that c-kit-positive neurons in the DRG belong to a functional subpopulation. The c-kit receptor protein was presented on the membrane of processes and growth cones in neurons. When DRG cells of embryonic day 15.5 or 17.5 were cultured, the survival of c-kit-positive neurons was supported by SCF, nerve growth factor (NGF) or leukemia inhibitory factor. SCF and NGF synergistically supported the survival of c-kit-positive neurons at submaximal concentrations. c-kit-positive DRG neurons from neonatal mice survived without addition of any factor in culture, suggesting that the requirement for trophic support in c-kit-positive neurons changes during development.
Hirata
T
T
Department of Pathology, Osaka University Medical School, Suita, Japan.
Kasugai
T
T
Morii
E
E
Hirota
S
S
Nomura
S
S
Fujisawa
H
H
Kitamura
Y
Y
D000367:Age Factors; D000818:Animals; D002452:Cell Count; D005727:Ganglia, Spinal / Q000378:metabolism*; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D051379:Mice; D008810:Mice, Inbred C57BL; D009414:Nerve Growth Factors / Q000494:pharmacology; D009474:Neurons / Q000378:metabolism; D011518:Proto-Oncogene Proteins / Q000378:metabolism*; D019009:Proto-Oncogene Proteins c-kit; D012333:RNA, Messenger / Q000378:metabolism; D020794:Receptor Protein-Tyrosine Kinases / Q000378:metabolism*; D016184:Receptors, Colony-Stimulating Factor / Q000378:metabolism*; D013116:Spinal Cord / Q000378:metabolism; D013373:Substance P / Q000378:metabolism
D009414:Nerve Growth Factors; D011518:Proto-Oncogene Proteins; D012333:RNA, Messenger; D016184:Receptors, Colony-Stimulating Factor; D013373:Substance P; D019009:Proto-Oncogene Proteins c-kit; D020794:Receptor Protein-Tyrosine Kinases