Metabolic rate of membrane-permeant diacylglycerol and its relation to human resting T-lymphocyte activation
| Autor: | Masahiro Oka, Kimihisa Yoshida, Yoshinori Asaoka, Yasutomi Nishizuka |
|---|---|
| Rok vydání: | 1991 |
| Předmět: |
medicine.medical_specialty
Cell Membrane Permeability Diacylglycerol lipase T-Lymphocytes Gene Expression In Vitro Techniques Biology Lymphocyte Activation Diglycerides chemistry.chemical_compound Internal medicine medicine Humans Diglyceride Receptor Protein kinase C Diacylglycerol kinase Multidisciplinary Dose-Response Relationship Drug Ionomycin Biological Transport Receptors Interleukin-2 Phosphatidic acid T lymphocyte Endocrinology chemistry Phorbol biology.protein Tetradecanoylphorbol Acetate Research Article |
| Zdroj: | Proceedings of the National Academy of Sciences. 88:8681-8685 |
| ISSN: | 1091-6490 0027-8424 |
| Popis: | DL-1,2-Dioctanoylglycerol (1,2-DiC8) added to human peripheral resting T lymphocytes was rapidly metabolized to produce octanoic acid and further to small molecules, probably by the action of diacylglycerol lipase and/or nonspecific esterase. Only a small portion was converted to the corresponding phosphatidic acid or was isomerized to 1,3-DiC8 before being metabolized. The uptake of 1,2-DiC8 by the cell was apparently fast, and the rate of disappearance of 1,2-DiC8 was dependent on the cell densities; at a higher density of T lymphocytes 1,2-DiC8 was removed quickly, whereas at a lower cell density 1,2-DiC8 remained for a longer period of time. With a fixed amount of 1,2-DiC8 added, the extent of interleukin 2 receptor alpha-subunit (IL-2R alpha) expression was inversely related to the cell density and proportional to the duration of exposure of the cells to 1,2-DiC8. Repeated doses of 1,2-DiC8 potentiated IL-2R alpha expression. In contrast, a single dose of phorbol 12-myristate 13-acetate caused T-lymphocyte activation to similar extents irrespective of the cell density, probably because the phorbol ester was not metabolized and remained in membranes. The available evidence supports a proposal made in a previous paper and indicates that the sustained activation of protein kinase C for at least the first 3-4 hr is essential for the activation of resting T lymphocytes. |
| Databáze: | OpenAIRE |
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