title: Influence of membrane fluidity changes upon the imprinting of polypeptide hormones in Tetrahymena.
abstract: Hormonal imprinting is a physiological phenomenon, in which after the first encounter the receptorial and functional responses of a cell change for future occasions. The present experiments demonstrate (using Tetrahymena as a model cell) that the imprinting is very sensitive to the changes in membrane physical state. Cultivation of Tetrahymena cells in 28 or 15 degrees C or in ergosterol-supplemented media caused only quantitative differences in the imprinting; however, the process of cooling (shift-down) or reheating (shift-up) resulted in a false reaction. The combined treatment by ergosterol and cooling completely abolished the imprinting. These results indicate that hormonal imprinting is a membrane-dependent process.
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D004875:Ergosterol / Q000494:pharmacology; D007328:Insulin / Q000378:metabolism / Q000494:pharmacology; D007447:Invertebrate Hormones / Q000502:physiology*; D008560:Membrane Fluidity / Q000187:drug effects; D011972:Receptor, Insulin / Q000032:analysis; D013696:Temperature; D013768:Tetrahymena / Q000166:cytology / Q000378:metabolism / Q000502:physiology*; D013972:Thyrotropin / Q000378:metabolism / Q000494:pharmacology
chemical_list: D007328:Insulin; D007447:Invertebrate Hormones; D013972:Thyrotropin; D011972:Receptor, Insulin; D004875:Ergosterol