title: The effect of endotoxins and enzymes in vitro on the release of gingival histamine.
abstract: Gingival samples removed from fifteen Beagle dogs were sectioned into small pieces, parts of which served as the uncultured piece; the remaining pieces were organ cultured for four hours at 37 degrees C in MEM control, compound 48/80, endotoxins, protease, collagenase, hyaluronidase, trypsin and chymotrypin media. Uncultured and cultured tissues and spent media were analyzed spectrofluorometrically for histamine content. The uncultured gingiva contained a mean of 2.80 mug histamine/g of tissue and was considered to contain 100% total histamine available for release. The percentages of histamine released into the medium were 5.4% for culture control, 57.3% for compound 48/80, 5.4% for endotoxins, 77.3% for protease, 16.1% for hyaluronidase, 24 for collagenase, 39.3% for trypsin, and 36.5% for chymotrypsin. When compared to the culture control, all test substances showed statistically significant histamine release (P less than 0.005 to P less than 0.0005) except for the endotoxins and for hyaluronidase (P greater than 0.05). The results demonstrate (1) that gingiva contains a potential source or reservoir of histamine, presumably in mast cells, and when appropriately challenged in vitro can release this histamine; (2) no direct effect of endotoxins on histamine release in vitro, (3) that all enzymes tested except hyaluronidase resulted in significant histamine release. The results of this in vitro study support a thesis that enzymes are active in the early events of gingival inflammation.
mesh_terms: D000818:Animals; D002918:Chymotrypsin / Q000494:pharmacology; D004285:Dogs; D004305:Dose-Response Relationship, Drug; D004731:Endotoxins / Q000494:pharmacology*; D004798:Enzymes / Q000494:pharmacology*; D005881:Gingiva / Q000378:metabolism*; D006636:Histamine Release / Q000187:drug effects*; D006821:Hyaluronoglucosaminidase / Q000494:pharmacology; D003012:Microbial Collagenase / Q000494:pharmacology; D010447:Peptide Hydrolases / Q000494:pharmacology; D014357:Trypsin / Q000494:pharmacology; D003189:p-Methoxy-N-methylphenethylamine / Q000494:pharmacology
chemical_list: D004731:Endotoxins; D004798:Enzymes; D003189:p-Methoxy-N-methylphenethylamine; D006821:Hyaluronoglucosaminidase; D010447:Peptide Hydrolases; D002918:Chymotrypsin; D014357:Trypsin; D003012:Microbial Collagenase