OBJECTIVETo establish a new culture system for mouse tooth germs in chick embryo.

METHODSThe mandibular first molar germ fragments of 15 embryonic days' Kunming mouse embryo were implanted into the lateral mesenchyme of 4-5 days' chick embryo wing buds in ove. Eggs were reincubated and implanted tissues were examined by histochemistry.

RESULTSThe cultured tooth germ development continued from cap stage to latest bell stage. The ameloblast and the odontoblast all differentiated maturely and secreted matrix.

CONCLUSION4-5 days' wing buds chick embryo could serve as developing the mouse tooth germs and demonstrate well physiological process of differentiation and morphogenesis.

Ameloblasts ; Animals ; Chick Embryo ; Mice ; Molar ; embryology ; Odontoblasts ; Tooth Germ ; embryology

OBJECTIVETo quantitatively compare the relationship between the congenital cleft palate and development of the palatal shelf.

METHODSFifty two pairs palatal shelves were macroscopic measured, and 60 series coronal sections were microscopically measured, which were precisely orientated in the coronal plane and serially sectioned at 7 micro m thickness. With the aid of computer imaging analysis system the widths and areas of the palatal shelves in vertical and coronal direction, the maximal areas of the palatal bone and palatal process and alveolar process were measured and compared quantitatively between the cleft group and non-cleft group.

RESULTSThe widths and areas of palatal shelves in cleft foetuses showed significant reduction macroscopically and microscopically as well as the maximal areas of the palatal bone, in addition, both of two processes of the maxilla showed significant developmental deficiency.

CONCLUSIONSThe palatal shelves show significant developmental hypoplasia in three dimension directions, which have significant correlation between palatal cleft and trisomic condition.

Animals ; Cleft Palate ; embryology ; genetics ; Female ; Image Processing, Computer-Assisted ; Mice ; Palate ; anatomy & histology ; embryology ; Trisomy

To investigate the expression of phospholipase C-gamma1 (PLC-gamma1) in mouse embryonic tissues, serial tissue sections were prepared routinely for immunocytochemistry for PLC-gamma1. The results showed that PLC-gamma1 was expressed in the cartilage, skeletal muscles, myocardium, the collecting tubule of the kidney, connective tissues and the brain, suggesting the important role PLC-gamma1 and the related signal pathway may play in the development of mouse embryonic tissues.
Animals ; Brain ; embryology ; enzymology ; Cartilage ; embryology ; enzymology ; Embryo, Mammalian ; enzymology ; Female ; Fetal Heart ; enzymology ; Immunohistochemistry ; Kidney ; embryology ; enzymology ; Mice ; Muscle, Skeletal ; embryology ; enzymology ; Phospholipase C gamma ; biosynthesis ; Pregnancy

gp130-mediated signaling is involved in both chondrogenesis and osteogenesis, but its direct role in the formation of embryonic Meckel's cartilage and associated mandibular development has not yet been elucidated. In this study, we examined the influence of gp130 ablation on the developing mandibular Meckel's cartilage by evaluating the morphological and histological changes as well as the gene expression patterns in developing embryonic gp130-/- mice. The ablation of the gp130 gene showed no change in region-specific collagen mRNA expression except for a slight delay in its expression but caused shortened embryonic Meckel's cartilage, delayed hypertrophic chondrocyte maturation and subsequent bony replacement with characteristic bending of the intramandibular Meckel's cartilage. The bending of Meckel's cartilage led to a narrow mandibular arch at the rostral area with poor cortical plate formation. These findings indicate that gp130-mediated signaling is important for the normal morphogenesis of Meckel's cartilage and subsequent mandibular development.
Animals ; Body Patterning ; Cartilage/embryology/metabolism/*physiology ; Collagen ; Cytokine Receptor gp130/genetics/*physiology ; Mandible/embryology/metabolism/*physiology ; Mice ; Mice, Knockout

OBJECTIVETo examine the change of Smoothened (Smo) expression in the retinofugal pathway and in the growth cones during the period of embryonic day 13 (E13) to E15.

METHODSSmo expression in the chiasm and growth cones was observed by fluorescent immunostaining and retinal explant culture.

RESULTSOn E13 and E14, Smo was expressed moderately in the retina and optic disc, and in the corner of the retina, Smo expression was especially dense. On E13, Smo expression was detected in the optic nerves and ventral diencephalon, but only in the superficial region of the optic tract on E14. Smo was also detected in the stem and filopodia of the growth cones in the retinal explant culture during this period.

CONCLUSIONSmo expression changes in different developmental phases, suggesting that Smo might play a role in signal optic axon growth during the development of the retinofugal pathway.

Animals ; Fluorescent Antibody Technique ; Mice ; Mice, Inbred C57BL ; Optic Chiasm ; cytology ; embryology ; metabolism ; Optic Nerve ; cytology ; embryology ; metabolism ; Receptors, G-Protein-Coupled ; biosynthesis ; Retina ; cytology ; embryology ; metabolism ; Smoothened Receptor ; Visual Pathways ; cytology ; embryology ; metabolism

OBJECTIVETo understand the function of Sonic hedgehog in chiasm development in mouse embryos of embryonic day 13 (E13) to E15.

METHODSBrain slices of E13-E15 mouse embryos containing the optic pathway from the eyes to the optic tract were prepared and cultured in DMEM/F12 in the presence of 10% fetal bovine serum at 37 degrees in a rolling incubator for 5 h. The antibody to Shh was added into the culture medium of the slices in the treatment group, while no additional chemical or only normal mouse IgG was added in the control groups. After culture, the brain slices were fixed and a DiI granule was inserted into the optic disc in one eye. Seven days later, the tissue overlying the chiasm was removed to expose the DiI-labeled chiasm for observation under confocal microscope, and the images were analyzed by METAMORPH software.

RESULTSShh antibody treatment produced a reduction of crossing of the earliest retinal axons at the midline of E13 chiasm, and the uncrossed axons were also influenced by Shh antibody at E15.

CONCLUSIONShh executes a transient but important function in axon decussation in the early stage of mouse optic chiasm development and signals axon turning in the later stage.

Animals ; Antibodies ; immunology ; metabolism ; Hedgehog Proteins ; immunology ; metabolism ; Mice ; Neural Pathways ; embryology ; metabolism ; Optic Chiasm ; embryology ; metabolism ; Retina ; embryology ; metabolism ; Signal Transduction ; Tissue Culture Techniques

The aim of the present paper is to better understand the mechanism of hematopoietic development through studying the biological characteristics of hematopoietic progenitor cells at different stages of development. Firstly, the c-kit expression levels of the mononuclear cells from murine embryonic aorta-gonad-mesonephros (AGM) region at embryonic day (E)10.5 and E11.5, fetal liver (FL) at E12.5, E14.5, E16.5, E18 and bone marrow (BM) were assayed with fluorescence activated cell sorting (FACS). Secondly, hematopoietic progenitor cells derived from AGM at E10.5, FL at E14.5 and BM were isolated by using c-kit microbeads. Isolated c-kit(+) population cells from AGM, FL and BM were then co-cultured with E14.5 FL-derived stromal cells in transwell co-culture system in vitro. After 3, 7, 10 days of co-culture, numerous floating cells were generated. The floating cells generated in transwell inserts were collected for FACS cell count, migration activity detection and colony forming unit (CFU) formation assay. The results showed that the c-kit was highly expressed in E10.5 AGM, with the percentage of c-kit(+) cells declining during AGM development. c-kit expression was highly expressed again in E12.5 FL, declining along with the progressive development of the FL region. Co-cultured with FL-derived stromal cells, E10.5 AGM-derived c-kit(+) cells produced the highest number of hematopoietic cells, while BM-derived c-kit(+) cells produced the lowest number of hematopoietic cells. Compared with E10.5 AGM-derived c-kit(+) cells, E14.5 FL- and BM- derived c-kit(+) cells inclined to differentiate after 7 to 10 days of culture in vitro. E10.5 AGM and E14.5 FL-derived c-kit(+) cells exhibited a higher migration activity than BM-derived c-kit(+) cells. Moreover, E10.5 AGM-derived c-kit(+) cells showed a higher ability to form mixed colony-forming unit (CFU-Mix) colony. In conclusion, compared with FL- and BM-derived c-kit(+) cells, E10.5 AGM-derived c-kit(+) hematopoietic progenitor cells exhibit better proliferation, migration potential, and have a higher ability to maintain the undifferentiation state in vitro, providing an insight into their clinical manipulation.
Animals ; Aorta ; embryology ; Coculture Techniques ; Colony-Forming Units Assay ; Gonads ; embryology ; Hematopoiesis ; Hematopoietic Stem Cells ; cytology ; Mesonephros ; embryology ; Mice ; Proto-Oncogene Proteins c-kit ; metabolism ; Stromal Cells ; cytology

The purpose of this study was to describe the luminal development of the murine eustachian tube and middle ear. Thirty specimens, aging from gestational day 11 to postnatal day 21, were investigated through the light microscopic observations. The present study also used digitizer, computer, and serially sectioned temporal bone specimens for three-dimensional reconstruction to measure the volume of the eustachian tube and middle ear cavity at different gestational and postnatal ages. The first pharyngeal pouch elongated during gestational day 12 to form the tubotympanic recess. Between gestational day 13 and 14 this tubotympanic recess extended to the middle ear area. A rapid increment in the volume of the tubotympanic recess was noted between gestational day 15 and 16. At this age, a definite division of the tubotympanic recess into the eustachian tube and middle ear cavity was observed. During the postnatal period, the maximum change of the middle ear volume was noted on postnatal day 11 when the mesenchymal tissue in the middle ear cavity disappeared completely.
Animal ; Ear, Middle/anatomy & histology/*embryology/growth & development ; Eustachian Tube/anatomy & histology/*embryology/growth & development ; Female ; Male ; Mice ; Mice, Inbred BALB C ; Pregnancy

Cytoplasmic Cu/Zn superoxide dismutase (SOD1) is an antioxidant enzyme that converts superoxide to hydrogen peroxide in cells. Its spatial distribution matches that of superoxide production, allowing it to protect cells from oxidative stress. SOD1 deficiencies result in embryonic lethality and a wide range of pathologies in mice, but little is known about normal SOD1 protein expression in developing embryos. In this study, the expression pattern of SOD1 was investigated in post-implantation mouse embryos and extraembryonic tissues, including placenta, using Western blotting and immunohistochemical analyses. SOD1 was detected in embryos and extraembryonic tissues from embryonic day (ED) 8.5 to 18.5. The signal in embryos was observed at the lowest level on ED 9.5-11.5, and the highest level on ED 17.5-18.5, while levels remained constant in the surrounding extraembryonic tissues during all developmental stages examined. Immunohistochemical analysis of SOD1 expression on ED 13.5-18.5 revealed its ubiquitous distribution throughout developing organs. In particular, high levels of SOD1 expression were observed in the ependymal epithelium of the choroid plexus, ganglia, sensory cells of the olfactory and vestibulocochlear epithelia, blood cells and vessels, hepatocytes and hematopoietic cells of the liver, lymph nodes, osteogenic tissues, and skin. Thus, SOD1 is highly expressed at late stages of embryonic development in a cell- and tissue-specific manner, and can function as an important antioxidant enzyme during organogenesis in mouse embryos.
Animals ; Cerebral Cortex/embryology/enzymology ; Copulation ; Cytoplasm/*enzymology ; Embryonic Development/*physiology ; Female ; Immunohistochemistry ; Lung/embryology/enzymology ; Male ; Mice ; Mice, Inbred ICR ; Organogenesis/*physiology ; Pregnancy ; Stomach/embryology/enzymology ; Superoxide Dismutase/deficiency/genetics/*metabolism

The GATA family proteins are a group of zinc finger transcription factors that are expressed in human and mammalian animals and play an important role in mammalian organ morphogenesis, cell proliferation and sex differentiation. GATA-4 and GATA-6 have been identified in the ovaries and testes of humans, mice, pigs and chickens. GATA-4 contributes to fetal male gonadal development by regulating the genes that mediate Müllerian duct regression and the onset of testosterone production. GATA-4 and GATA-6 are localized in and regulate the function of the ovarian and testicular somatic cells of fetal mice, especially granulosa cells, thecal cells, Sertoli cells and Leydig cells. GATA-4 is also present in the germ cells of fetal and prepubertal mice.
Animals ; Chickens ; Female ; GATA4 Transcription Factor ; metabolism ; GATA6 Transcription Factor ; metabolism ; Humans ; Male ; Mice ; Ovary ; embryology ; Reproduction ; Swine ; Testis ; embryology ; Transcription Factors ; classification