The physiological effects of hypoxia on the erythrocytes of the chick embryo☆

[摘要] Chickembryosranginginagefrom6to18dayswereexposedtoalowoxygen(13%)environmentfor1day.Embryoswereanalyzedoneachodddayofincubationbetweenday7andday19forchangeswithinthebloodpicture.Testsincludeddeterminationsofthenumberoferythrocytes,theerythrocytevolume,thehemoglobinconcentration,theerythrocytestages,andembryonicweightsandstages.Followingalowoxygenincubationembryosofgreaterthan12daysofagedemonstratedanenhancementofboththeerythrocyteandhemoglobinconcentrations.Thisresponsewasheightenedastheembryoaged.Themeanerythrocytevolumewassignificantlylargerinthe7-,11-,15-,and17-dayembryosexposedto13%oxygenascomparedwiththeircontrols.Changesinerythrocytestagewerealsonotedinoxygen-deficientembryos.IngeneralthemostmatureRBCstagespresentatanytimecomprisedagreaterproportionofthetotalpopulationincontrolanimalsascomparedwiththestressed.Embryonicweightandstagewereminimallyaffectedbythehypoxicenvironment.Theriseinerythrocyteandhemoglobinlevelsinolderanimalsfollowinga1-dayexposureto13%oxygenwasthoughttobecausedbytheactivationofcertainhomeostaticmechanismsdevelopingduringthesecondhalfofincubation.Thedifferentiationofthemetanephrickidneywasconsideredanimportanteventintheestablishmentofthesemechanisms.

[学科分类] 生物科学（综合）