Development of cholinergic innervation in the hippocampal formation of the rat: I. Histochemical demonstration of acetylcholinesterase activity☆

[摘要] Thepostnataldevelopmentofacetylcholinesterase(AChE)activityinthehippocampalformationofthedevelopingratbrain,asdemonstratedhistochemicallybythecopper-thiocholinetechnique,servesasamarkerfortheingrowingcholinergicafferentfibers.Thediscretelaminarpatternofstainingcharacteristicoftheadulthippocampalformationdevelopsentirelyafterbirth.Staindepositisobservableearliest(about4daysafterbirth)attheseptalendofthehippocampus.Duringthefollowingweek,AChEactivitycanbedemonstratedinsuccessivelytemporalsegmentsuntil,about11daysafterbirth,allpartsofthehippocampalformationexhibitactivity.Withineachsegment,thepatternofdevelopingactivitysuggestsassociationwiththreedistinctfiberprojectionsemanatingfromthefimbria,eachwithitsowncharacteristictimeofappearanceandrateofgrowth:(1)aprojectionthroughstratumoriensofhippocampusregioinferiortostratumoriensofregiosuperior;(2)fiberswhichcrossstraumpyramidaleofregioinferior,runinthesuprapyramidalzoneofthatregionandcontinueintothesupra-andinfragranularzonesintheexternalleafofthedentategyrus;(3)aprojectionthroughstratumoriensofregioinferiorwhichcontinuesintothesupra-andinfragranularzonesintheinternalleafofthedentategyrus.

[学科分类] 生物科学（综合）