The development of structure and transport systems of the fetal rabbit intestine☆
[摘要] SegmentsofsmallintestinefromthefetalrabbitwereincubatedinamediumcontainingC14-labeledsugaroraminoacid(1mM)andtissueuptakewasmeasured.Intestineobtainedfromfetalrabbitsatthe22nddayofgestationwascapableofaccumulatingα-methylglucose,valine,methionine,andlysineagainstsmallbutdistinctconcentrationgradients.Astheembryosdeveloped,thecapacityoftheintestinetoaccumulatethesesubstancesincreased2–5-fold.Incontrast,betainedidnotequilibratewithtissueH2Ountilthe26thdayofgestationandwasnotaccumulatedactivelyuntilthe28thday.Thisprovidesstrongevidencefortheexistenceofaseparatebetainetransportsystem.Bothl-prolineandglycinewereactivelyaccumulatedbyfetalintestinepriortothedevelopmentofabetainetransportsystem.Fromthe21stdaytoterm,thereweremarkedmorphologicalchangesintheintestinalepitheliumasseenbylightandelectronmicroscopy.Thedevelopmentofvillousandmicrovillousstructureprovidedthedevelopingintestinewithanenormouslyincreasedabsorptivesurfacearea.
[发布日期] [发布机构]
[效力级别] [学科分类] 生物科学（综合）
[关键词] [时效性]
