Two erythropoietic microenvironments and two larval red cell lines in bullfrog tadpoles☆

[摘要] PreviousworkhasshownthatRanacatesbeianatadpoleshavetwoerythropoieticsites:mesonephrickidneyandliver.Bothsitesapparentlyareactivethroughoutlarvallife.Amongthepleomorphiclarvalredbloodcells(RBCs)weobservetwomorphologicaltypeswhichdifferinthelarvalhemoglobins(Hb)thattheycontain.Onetypeisanoblong,ovalRBCwithanacentricnucleusandcontainsthelarvalHbwhichisslowestmigratingonelectrophoresisatbasicpH.ThisRBCtypeemanatesfromthekidneys.Theothertype,whichisellipticalinshape,withacentralnucleus,containsthreeotherlarvalHbsandemanatesfromtheliver.Histologicalsectionsofkidneyandliverrevealerythropoieticfociofdifferingcellularcompositionandconfiguration.WehavehypothesizedthatchoiceofRBCandHbtypesisdeterminedinpartbythedifferenterythropoieticmicroenvironments.Insupportofthishypothesisisourfindingthat,inorgancultures,livercoculturedwithkidneyundergoesashiftinitsHbpattern.PartoftheshiftistowardtheHbtypewhichistheproductofkidneyerythropoiesis.

[学科分类] 生物科学（综合）

[关键词] EGTA;ethyleneglycol bis(β-aminoethyl ether) N;N′-tetraacetic acid;Hb;hemoglobin;Hepes;N-2-hydroxyethyl piperazine-N′-2-ethanesulfonic acid;RBC;red blood cell