PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Embryonic Induction”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 73 records · Page 4Linked to original sources
PubMed1983

Transferrin as a fetal growth factor: acquisition of responsiveness related to embryonic induction.

Differentiation of the metanephric mesenchyme, which is triggered by an inductive tissue interaction, has been shown to proceed in a chemically defined medium containing transferrin. Here, we report that neither transferrin-depleted serum nor a chemically defined medium devoid of transferrin promote differentiation and that activity can be restored by the addition of transferrin. It thus appears that we have identified the serum factor required for kidney differentiation. Transferrin seems to affect differentiation by stimulating cell proliferation. We show by using an organ-culture model system that only mesenchymes induced to differentiate by the 24-hr tissue interaction respond to transferrin by proliferation and differentiation, whereas uninduced mesenchymes remain unresponsive. The inductor tissue used is not responsive to transferrin. Thus, the data suggest that the short-range cell-mediated tissue interaction acts by making the nephrogenic mesenchyme responsive to the long-range mediator, which is transferrin. Transferrin is suggested to be an important circulating growth factor required for proliferation during embryogenesis.

Animals↗
PubMed1984

Analysis of embryonic induction by using cell lineage markers.

Three distinct inductive interactions have been demonstrated in early embryos of Xenopus laevis: mesoderm induction, dorsalization and neural induction. The experiments were done with grafts from embryos uniformly labelled with passive cell lineage markers, either FITC-lysine-dextran (FLDx) or horseradish peroxidase (HRP), which allow the provenance of regions to be determined down to the single cell level. In each case the fate of the target tissue in the presence of the appropriate inductor was quite different from the fate in normal development.

Animals↗
PubMed1981

A rapid experimental method to study primary embryonic induction.

The technique described here is a combination of the sandwich-method and cell culture. It allows one to know quickly whether induction occurred or not (48 h if cell spreading is considered, 4-5 days if morphological differentiation is observed). The dissociation of the explants soon after induction does not disturb their inductive pattern. Moreover, this method allows a daily observation of the morphological events and study at the cellular and/or molecular level.

Animals↗
PubMed1984

Cell-to-cell contact in primary embryonic induction: effects of lectin on electrical coupling and neural induction.

The effects of lectin (concanavalin A; ConA) on the electrical coupling between inducing chorda-mesoderm and reacting ectoderm cells, and the realization of neural induction were investigated. The electrical coupling between cells of the chorda-mesoderm of the late gastrula (stage 13b) and the competent ectoderm or Con-A-treated ectoderm of the early gastrula (stage 12a) was measured. Neural induction was tested with ectoderm explants which had been combined with the inducing chorda-mesoderm for 1, 3 and 6 h. Electrical coupling was observed after 3 h. By 6 h, the coupling ratio had recovered to the same level as that between the homogeneous germ-layer cells. However, the electrical coupling did not recover in the combinant with Con-A-treated ectoderm. This suggests that Con-A disturbs close cell contact between the ectoderm and chorda-mesoderm cells. Neural induction was realized in the ectoderm which was combined with chorda-mesoderm for more than 3 h; this occurred parallel to the recovery of electrical coupling. In contrast, Con-A treatment (50 micrograms/ml) of the competent ectoderm for 30 min prevented neural induction. After 3 h of contact, the neural induction of Con-A-treated ectoderm was only one-third of that of the control ectoderm. The present study suggests that cellular contact between the inducing mesoderm and the ectoderm target cells plays an important role in the realization of neural induction.

Animals↗