All-trans-Retinal Stimulates Superoxide Release and Phospholipase C Activity in Neutrophils without Significantly Blocking Protein Kinase C

• Published in: Proceedings of the National Academy of Sciences - PNAS 1986-10, Vol.83 (20), p.7673-7677
• Main Authors: Lochner, Janis E., Badwey, John A., Horn, Wilhelm, Karnovsky, Manfred L.
• Format: Article
• Language: English
• Subjects: Biological and medical sciences; Cell physiology; Cytosol; Formates; Free Radicals; Fundamental and applied biological sciences. Psychology; Inositol phosphates; Inositol Phosphates - metabolism; Inositols; Miscellaneous; Molecular and cellular biology; Neutrophils; Neutrophils - drug effects; Neutrophils - metabolism; Phorbol esters; Phosphates; Phosphatidylinositols; Protein Kinase C - analysis; Retinaldehyde - pharmacology; Retinoids; Retinoids - pharmacology; Superoxides; Superoxides - metabolism; Tetradecanoylphorbol Acetate - pharmacology; Type C Phospholipases - analysis
• ISSN: 0027-8424; 1091-6490
• DOI: 10.1073/pnas.83.20.7673

all-trans-Retinal was previously shown to stimulate high levels of superoxide release by guinea pig neutrophils. When the cells, previously labeled with [3H]inositol, are treated with all-trans-retinal, they exhibit a decrease in the levels of [3H]inositol phospholipids and an increase in the accumulation of [3H]inositol phosphates. The maximal accumulation of inositol phosphates and the optimal rate of superoxide release occurred together at ≈ 7 min after stimulation. The levels of [3H]inositol phosphates accumulated were comparable to those observed when the cells were stimulated with a chemotactic peptide. In direct measurements, using concentrations that stimulate intact cells maximally, all-trans-retinal was found not to inhibit protein kinase C from the cytosol of neutrophils significantly. This contrasts with the situation with this kinase obtained from other sources. These observations represent additional effects of vitamin A on cells.