Retrograde axonal transport in lateral motor neurons of the chick embryo prior to limb bud innervation☆

[摘要] Horseradishperoxidasewasinjectedintothedistallimbbudsof3-,3.5-,and4-daychickembryosandwasallowedtodiffuseintothepathofoutgrowingaxons.Inthemajorityoftheembryosinjected,reactionproductwasfoundincellsoftheventralspinalcordipsilateraltotheinjectionsite.Thereactionproductinthemostclearlystainedcellsappearedsmoothanddiffuseratherthanthetypicalgranularappearancefoundinlaterembryosandadults.Agranularbackgroundwasseenin4-dayembryos,however,althoughdistinctgranularcelloutlineswereinfrequent.Thisstudyindicatesthatretrogradeaxonaltransportisaveryearlycellularfeatureduringneurogenesis,demonstrablealmostfromtheinceptionofneuriteoutgrowth.Itisspeculatedthatthistransportcapacitymightfunctioninrelayingpositionalinformationfromgrowingfibertipsbacktocellbodiestoaidintheformationofspecificsynapticconnectionsoringuidingdirectedaxonalgrowth,oritmayprovideameansfortrophicinteractionsvitaltothesurvivaloftheyoungneuroblast.

[学科分类] 生物科学（综合）