Comparison of Defolliculated Oocytes and Intact Follicles of the Cockroach Using the Vibrating Probe to Record Steady Currents

[摘要] FolliclecellswereremovedbydissectionfromearlyvitellogenicoocytesofthecockroachBlattellagermanica.Thevibratingprobewasusedtorecordsteadycurrentsfrom19defolliculatedoocytesand19intactfolliclesofthesamedevelopmentalstage.Defolliculatedoocytesgeneratedcurrentsthatwerestableanddistinguishable(byintensityorselectivedirection)frombackgroundreferencevalues.Distributionsoftheintensitiesofreferencevaluesandexperimentalvalueswere,ingeneral,similarinbothintactanddefolliculatedpreparations.Thepatternsofcurrentsgeneratedbypreparationsrecordedinthemid-sagittalplanewereanalyzedforbothdefolliculatedoocytes(n=8)andintactfollicles(n=10).Thelarger,generallymorematurepreparationsinbothgroupsgeneratedpatternsofcurrentsimilartothepatternseeninmid-vitellogenicfollicles(focusedinwardnearthegerminalvesicle(GV),thepresumptiveventralside,andbroadlyoutwardontheapo-GVside,thepresumptivedorsalside).Smallersizedpreparationsinbothgroupsshowedinwardoroutwardcurrentontheapo-GVaspectand,typically,inwardcurrentattheGV.Onlytwodefolliculatedoocytes,andnointactfollicles,appearedtogenerateoutwardcurrentattheGV,andwebelievethisobservationresultedfromrecordingslightlyoutsidethemid-sagittalplane.Weconcludethatpreparationsduringearly-vitellogenesisinitiallygeneratecurrentswithoutanasymmetricpatternandthattheinwardfluxattheGVisthefirststepindevelopingpatternsofcurrents.Theresultssuggestthattheoocyte(andnotthefolliclecellepithelium)isresponsibleforgeneratingthevariouspatternsofcurrentsobservedinearly-vitellogenicstages.Attheendofearly-vitellogenesis,thefolliclecellepitheliumbeginstoadheretightlytotheoocyte.Thepossibilityisconsideredthatthefolliclecellsmayinfluencethecurrentsgeneratedduringmid-vitellogenesis.

[学科分类] 生物科学（综合）