Migrating luteinizing hormone-releasing hormone (LHRH) neurons and processes are associated with a substrate that expresses S100.
Luteinizing hormone-releasing hormone (LHRH) containing neurons arise in the region of the medial olfactory placode and migrate into the developing olfactory bulbs and basal forebrain along branches of the terminal and vomeronasal nerves. The neurons ultimately come to reside in olfactory and septo-preoptic areas and project extensively to several brain regions, including the preoptic area and median eminence. The present study examined the expression of a glial-associated guidance molecule, S100, as a possible substrate for this migration. Monodelphis domestica (the Brazilian grey, short-tailed opossum) was studied since this species gives birth to very immature, young, allowing access to early periods of mammalian forebrain development. Immunoreactivity for both S100 and LHRH-containing neurons and fibers were observed to be closely associated along the entire LHRH migratory route from the vomeronasal organ to the septo-preoptic areas as early as the day of birth (PO). By P10, S100-immunoreactivity was also seen in areas containing LHRH-immunoreactive fibers such as the preoptic area and median eminence. We suggest that S100, a protein with neurotrophic properties in vitro, acts as a guidance molecule for migrating LHRH-immunoreactive neurons and elongating processes.
Cummings
D M
DM
Neuroscience Program, University of Virginia, Charlottesville 22903, USA.
Brunjes
P C
PC
D000818:Animals; D002465:Cell Movement / Q000502:physiology; D005904:Glial Fibrillary Acidic Protein / Q000032:analysis; D007987:Gonadotropin-Releasing Hormone / Q000032:analysis*; D007150:Immunohistochemistry; D008473:Median Eminence / Q000737:chemistry; D009296:Nasal Cavity / Q000737:chemistry; D009297:Nasal Mucosa / Q000737:chemistry; D009300:Nasal Septum / Q000737:chemistry; D009412:Nerve Fibers / Q000737:chemistry*; D009474:Neurons / Q000737:chemistry*; D009830:Olfactory Bulb / Q000737:chemistry* / Q000166:cytology; D009893:Opossums; D011301:Preoptic Area / Q000737:chemistry; D016548:Prosencephalon / Q000737:chemistry* / Q000166:cytology; D009418:S100 Proteins / Q000032:analysis*
D005904:Glial Fibrillary Acidic Protein; D009418:S100 Proteins; D007987:Gonadotropin-Releasing Hormone