title: Mast cell activation by group A streptococcal polysaccharide in the rat and its role in experimental arthritis.
abstract: Acute edematous responses were induced in Sprague-Dawley rats by the intravenous injection of group-specific polysaccharide (PS) isolated from group A streptococci. Thirty minutes after the intravenous injection of PS there was marked degranulation of subcutaneous and periarticular mast cells in all 4 feet, carbon particle labeling of adjacent venules, and an 8-fold increase in Evans blue dye content of the extremities. This acute reaction to PS was completely blocked by pretreatment with compound 48/80, but the polyarticular relapsing arthritis following the systemic injection of an arthropathic dose of streptococcal cell wall fragments containing large, covalently bound peptidoglycan-polysaccharide (PG-PS) was not blocked.
mesh_terms: D000818:Animals; D001170:Arthritis, Infectious / Q000209:etiology*; D004487:Edema / Q000139:chemically induced; D005260:Female; D005534:Foot Diseases / Q000139:chemically induced; D008407:Mast Cells / Q000187:drug effects / Q000473:pathology / Q000502:physiology*; D011135:Polysaccharides, Bacterial / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D013290:Streptococcal Infections; D013297:Streptococcus pyogenes; D003189:p-Methoxy-N-methylphenethylamine / Q000494:pharmacology
chemical_list: D011135:Polysaccharides, Bacterial; D003189:p-Methoxy-N-methylphenethylamine