am-356 and Leukemia

There are conflicting reports in the literature as to whether palmitoylethanolamide affects the function of mast cell-related cell lines in vitro, in contrast to the well-documented effects of this compound upon mast cell function in vivo. In the present study, we have reinvestigated the effects of palmitoylethanolamide upon antigen-induced release of [3H]serotonin and beta-hexosaminidase from rat basophilic leukemia RBL-2H3 cells and compared these effects with those of 2-arachidonoylglycerol, anandamide and R1-methanandamide. RBL-2H3 cells were sensitized with a monoclonal anti-DNP IgE, after which they were stimulated with antigen (DNP-HSA). Palmitoylethanolamide produced a small, but significant reduction in antigen-stimulated [3H]serotonin release at high concentrations, whereas anandamide was without effect. In contrast, 2-arachidonoylglycerol and methanandamide increased the antigen-stimulated release of both [3H]serotonin and beta-hexosaminidase. It is concluded that in RBL-2H3 cells, these cannabimimetic fatty acid derivatives do not have potent stabilizing effects upon antigen-induced degranulation.

Topics: Adjuvants, Immunologic; Amides; Animals; Arachidonic Acids; beta-N-Acetylhexosaminidases; Endocannabinoids; Enzyme Induction; Ethanolamines; Glycerides; Immunoglobulin E; Inflammation Mediators; Leukemia; Ligands; Mast Cells; Palmitic Acids; Polyunsaturated Alkamides; Rats; Serotonin; Tumor Cells, Cultured; Tumor Necrosis Factor-alpha