title: [Plant lectins and embryonic tissue factors as probes for studying the mechanisms of neural induction in amphibians].
abstract: Using various experimental techniques, we have demonstrated that animal pole ectoderm (APE) of Rana temporaria embryos at the stage of early gastrula is a good target tissue for testing the neuralizing (N) factors. In this respect R. temporaria APE is comparable with APE of some other amphibian species. We found that concanavalin A (con A), phytohemagglutinin (PHA) and embryonic brain-derived neuralizing factor (EBDNF; a factor extracted from the chick embryonic brain and partially purified) have a pronounced N-effect on the APE of R. temporaria. In order to analyse possible mechanisms of N-action of these factors, we have cultured APE explants for 3 or 18 h in the medium containing various concentrations of con A, PHA of EBDNF. All these factors could produce neuralization in 50% explants. However, the optimal concentration and time of exposure were different. This is an evidence for different mechanisms of reception and transmission of a N-signal in each particular case. It appears that the APE consists of several cell subpopulations which differ in their threshold sensitivity to the N-effect of studied agents.
authors.forename: A T
authors.initials: AT
authors.lastname: Mikhaĭlov
authors.forename: N A
authors.initials: NA
authors.lastname: Gorgoliuk
mesh_terms: D000663:Amphibians / Q000196:embryology*; D000818:Animals; D001685:Biological Factors / Q000494:pharmacology*; D001921:Brain / Q000196:embryology; D002642:Chick Embryo; D003208:Concanavalin A / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004475:Ectoderm / Q000502:physiology; D005775:Gastrula / Q000502:physiology; D037102:Lectins / Q000494:pharmacology*; D009420:Nervous System / Q000187:drug effects / Q000196:embryology*; D010835:Phytohemagglutinins / Q000494:pharmacology; D011896:Rana temporaria; D013997:Time Factors
chemical_list: D001685:Biological Factors; D037102:Lectins; D010835:Phytohemagglutinins; D003208:Concanavalin A
vernacular_title: Rastitel'nye lektiny i faktory iz émbrional'nykh tkaneĭ kak zondy dlia issledovaniia mekhanizmov neĭral'noĭ induktsii u amfibiĭ.