Development of “Normal” Dermatomes and Somatotopic Maps by “Abnormal” Populations of Cutaneous Neurons

Developmental Biology

Sheryl A. Scott¹  Guoying Wang¹ 

[1] Department of Neurobiology and Anatomy, University of Utah School of Medicine, Salt Lake City, Utah, 84132

关键词: dorsal root ganglia;    chick;    hindlimb;    sensory;    development;    dorsal horn;    somatotopy;    central projections;   

DOI  :  10.1006/dbio.2002.0824

学科分类：生物科学（综合）

来源: Academic Press

【 摘 要 】

Duringdevelopment,motorandsensoryaxonsgrowtoperipheraltargetswithremarkableprecision.Whereasmuchhasbeenlearnedaboutthedevelopmentofmotoneuronconnectivity,lessisknownabouttheregulationofcutaneousinnervation.Inadults,dorsalrootganglia(DRG)innervatecharacteristicskinregions,termeddermatomes,andtheiraxonsprojectsomatotopicallyinthedorsalhorn.Here,wehaveinvestigatedwhethercutaneousneuronsareselectivelymatchedwithspecificskinregions,andwhetherperipheraltargetskininfluencesthecentralconnectionsofcutaneousneurons.Toaddressthesequestions,weshiftedlimbbudsrostrallyinchickembryospriortoaxonoutgrowth,causingDRGstoinnervatenovelskinregions,andmappedtheresultingdermatomesandcentralprojections.Followinglimbshifts,cutaneousinnervationarosefrommorerostralandfromfewerDRGsthannormal,buttheoveralldermatomepatternwaspreserved.Thus,DRGsparceloutinnervationofskininaconsistentmanner,withnoindicationofmatchingbetweenskinandDRGs.Similarly,cutaneousnervesestablisheda“normal”somatotopicmapinthedorsalhorn,butinmorerostralsegmentsthanusual.Thus,theperipheraltargetskinmayinfluencethepatternofCNSprojections,butdoesnotdirectcutaneousaxonstospecificpopulationsofneuronsinthedorsalhorn.

【 授权许可】

Unknown