title: Mast cell secretion: differences between immunologic and non-immunologic stimulation.
abstract: Non-immunologic and immunologic stimulation of mast cells have been compared. Non-immunologic stimulation relys heavily on cellular Ca, is unaffected by neuraminidase treatment, shows a rapid inactivation, and elicits no increase in the incorporation of 3H-methyl groups into the lipid fraction. In contrast, stimulation by immunologic agents relys primarily on extracellular Ca, is inhibited by neuraminidase treatment, shows a comparatively slow rate of inactivation, and causes a significant increase in the incorporation of 3H-methyl groups into the lipid fraction. We found no evidence of cross-inactivation or desensitization between immunologic and non-immunologic agents. However, pretreatment of mast cells with neurotensin desensitized them to subsequent stimulation by compound 48/80. Our results support the hypothesis that immunologic and non-immunologic agents activate exocytotic mast cell secretion via separate mechanisms.
mesh_terms: D000818:Animals; D002118:Calcium / Q000502:physiology; D006636:Histamine Release / Q000187:drug effects; D007073:Immunoglobulin E / Q000276:immunology*; D066298:In Vitro Techniques; D008297:Male; D008407:Mast Cells / Q000276:immunology*; D008715:Methionine / Q000378:metabolism; D009439:Neuraminidase / Q000494:pharmacology; D009496:Neurotensin / Q000494:pharmacology; D010047:Ovalbumin / Q000276:immunology; D051381:Rats; D013268:Stimulation, Chemical; D003189:p-Methoxy-N-methylphenethylamine / Q000494:pharmacology
chemical_list: D007073:Immunoglobulin E; D009496:Neurotensin; D003189:p-Methoxy-N-methylphenethylamine; D010047:Ovalbumin; D008715:Methionine; D009439:Neuraminidase; D002118:Calcium