Role of heme oxygenace 1 in rodent embryogenesis

Abstract

Morphological and phenotype characterization of the Hmox1 gene-targeted mouse newlinewas done to investigate the role of Hmox1 in rodent embryogenesis. For this, the newlineHmox1 gene-targeted mouse colony was established and maintained in our animal newlinehouse. As an outset of establishing the colony, the breeding pattern of the HET newlineand WT mice were compared and this indicated similar pattern of reproduction. newlineLifespan studies indicated that KO mice have reduced lifespan. Partial prenatal newlinelethality of the KO mice was observed, as reported previously. Only 12% KO newlinesurvived at ~6 weeks age. Analysis of gestational age of lethality indicated that newlinemost of the KO embryos start dying at late gestation around 16.5dpc. The newlinepercentage of expected live KO embryos is 53% at 16.5dpc and only 11% at newline18.5dpc. Morphological characterization of the embryos from the wild type and newlineheterozygous matings indicated more variation in the crown-rump lengths and newlineembryo weights from the heterozygous matings. The placental weights from the newlineheterozygous matings have a wider range and have disorganized tissue structure in newlineboth KO and WT embryos. Thus placentation is defective in HET mice and newlinematernal Hmox1 level seems to be an important factor in normal development of newlineplacenta. Although no gross morphological anomalies are observed, the newlinevasculature appears to be reduced in many of the embryos from the heterozygous newlinematings especially the KO embryos. Interestingly, both normal and reduced newlinevasculature is observed in the embryos from heterozygous matings. Appearance of newlinethe reduced vasculature can be due to poorly developed blood vessels or less red newlineblood cells and the partial prenatal lethality of KO embryos could be due to poor newlinevasculature.