title: Effect of cell contact on regionalization of mouse embryos.
abstract: Cytochemical demonstrations of 5'-nucleotidase and alkaline phosphatase reveal the activity of these enzymes on regions of cell apposition from the late four-cell stage onward. These enzyme activities also appear on regions of artificial cell contact between aggregated embryos having more than four cells. Cytochemistry of single two-cell embryos does not reveal 5'-nucleotidase nor alkaline phosphatase activity, however, these enzyme activities appear at both the artificial and natural contacts in chimaeras of two two-cell embryos. We interpret these results as meaning: (1) that cell contact causes the regionalization of 5'-nucleotidase and alkaline phosphatase activity on the cell surface, (2) that these enzyme activities can be induced or enhanced by contact between two two-cell embryos, (3) that a signal is transmitted from the artificial to the natural contact.
authors.affiliation: Departamento de Biología, Universidad de Chile, Santiago.
authors.forename: S
authors.initials: S
authors.lastname: Sepúlveda
authors.forename: L
authors.initials: L
authors.lastname: Izquierdo
mesh_terms: D015720:5'-Nucleotidase / Q000378:metabolism; D000469:Alkaline Phosphatase / Q000378:metabolism; D000818:Animals; D001755:Blastocyst / Q000166:cytology / Q000502:physiology*; D002449:Cell Aggregation; D002450:Cell Communication; D002455:Cell Division; D002678:Chimera; D003513:Cycloheximide / Q000494:pharmacology; D005260:Female; D006651:Histocytochemistry; D051379:Mice; D008815:Mice, Inbred Strains
chemical_list: D003513:Cycloheximide; D000469:Alkaline Phosphatase; D015720:5'-Nucleotidase