Developmental Dynamics of the Definitive Mouse Placenta Assessed by Stereology

摘要: The mouse is an excellent model for studying the genetic basis of placental development, but analyses are restricted by lack quantitative data describing normal murine structure. This study establishes a technique generating such data, applies stereological techniques on systematic uniform random sections placentas between E12.5-E18.5 gestation (E1.0 = day vaginal plug), and considers results in context development labyrinth zone. Half each placenta was wax embedded exhaustively sectioned to determine absolute volumes zone (Lz), junctional (Jz), decidua using Cavalieri principle. other half resin 1-microm were used generate all volume, surface, length densities within Lz. Maximum volume reached E16.5, whereas Lz fraction increases until E18.5 at expense Jz decidua. Within Lz, surface area maternal blood spaces (MBS) expand rapidly E14.5 with no increase thereafter. In contrast, fetal capillary linear continues longer than that MBS. interhemal membrane separating circulations undergoes thinning prior expansion areas, achieving harmonic mean thickness 4.39 microm E18.5. specific diffusion capacity oxygen maximal which may be necessary support rapid growth end gestation.