Autonomous biochemical and morphological differentiation in fetal rat intestine transplanted at 17 and 20 days of gestation☆☆☆

[摘要] Themorphologicalandbiochemicaldevelopmentoffetalratintestinewasexaminedforupto5weeksfollowingtransplantationtosyngeneichostsat17and20daysofgestation.Intransplantsofbothages,normalvillibearingmatureenterocytesdeveloped.Inaddition,thedisaccharidaseslactase,maltase,andsucrase,aswellasalkalinephosphatase,underwentnormalpatternsofdevelopment.Lactaseactivity,initiallyhigh,fellsignificantly,whilemaltaseandsucraseactivitiesincreasedsignificantlyintheintervalbetween2and5weeksfollowingtransplantation.Duringthissameperiod,alkalinephosphatasedevelopedtheproximallylocated,high-activityform.Thetransplantedintestinealsodevelopednormaltopographicaldistributionsofenzymeactivities.Measurementofcorticosteronelevelsdemonstratedthat,exceptforatransientupsurgeatthetimeofoperation,hormonelevelsdidnotchangesignificantlyduringtheperiodoftransplantmaturation.Thesedataindicatethatthebrush-borderenzymesofthesmallintestinedevelopaccordingtoanintrinsicprogramwhichisalreadyestablishedasearlyas17daysofgestation.

[学科分类] 生物科学（综合）