Expressionoftheadhesionmolecules,ICAM-1,VCAM-1,NCAM,CD44,CD49d(VLA-4,αchain),andCDlla(LFA-1,αchain)onmouseoocytes,andpre-andperi-implantationstageembryoswasexam-inedbyquantitativeindirectimmunoliuorescencemicroscopy.ICAM-1wasmoststronglyexpressedattheoocytestage,graduallydecliningalmosttoundetectablelevelsbytheexpandedblastocyststage.NCAM,alsoexpressedmaximallyontheoocyte,declinedtoundetectablelevelsbeyondthemorulastage.Ontheotherhand,CD44declinedfromhighestexpressionattheoocytestagetoshowasecondmaximumatthecompacted8-cell/morula.Thismoleculeexhibitedhighexpressionaroundcontactareasbetweentrophecto-dermandzonapellucidaduringblastocysthatching.CD49dwashighlyexpressedintheoocyte,remainedsignificantlyexpressedthroughoutandafterblastocysthatchingwasexpressedonthepolartrophecto-derm.LikeCD44,CD49ddeclinedtoundetectablelevelsattheblastocystoutgrowthstage.ExpressionofbothVCAM-1andCDllawasundetectablethroughout.ThediametricaltemporalexpressionpatternofICAM-1andNCAMcomparedtoCD44andCD49dsuggestthatdynamicchangesinexpressionofadhesionmoleculesmaybeimportantforinteractionoftheembryowiththematernalcellularenvironmentaswellasforcontinuingdevelopmentandsurvivaloftheearlyembryo.
