Active calcium transport in the chick chorioallantoic membrane requires interaction with the shell membranes and/or shell calcium☆

[摘要] Directinteractionofthechorioallantoicmembrane(CAM)withtheoverlyingCa2+-richshellmembranesisnecessaryformaximalstimulationofCa2+transportbytheCAM.First,CAMdevelopingintheabsenceoftheshellandshellmembranes(inshell-lesscultureorinartificialairspacepreparations),whichdemonstratesnormalcytodifferentiation,developssignificantlyreducedCa2+transportcomparedtoeitherequatorialorairspaceCAMinovo.Second,exposureofshell-lessculturedCAMtoisolatedsectionsofCa2+-richshellmembranesfor5–7days,butnotfor30minor16hr,resultedinasignificantstimulationofCa2+transportintheimmediatelysubjacentCAMbutwaswithouteffectontransportfunctioninperipheralsectionsofculturedCAMexposedtoshellmembranes.NeitherelevatedCO2levelsnorapermissivehumoralenvironmentwassufficienttomaximallystimulatetransport.Additionally,wehavedemonstratedsignificantregionaldifferencesinCa2+transportbetweenequatorialandairspaceCAMinovo.OurdatadirectlydemonstratethatstimulationofCa2+transportisatimedependent,localphenomenon,requiringthepresenceoftheshellmembranesand/orshellCa2+ontheectodermalsideoftheCAMduringdevelopment.

[学科分类] 生物科学（综合）