Some properties of gingival 12-lipoxygenase activity in human and dog.
Arachidonate lipoxygenase activity in gingival tissue was investigated and compared with that of enzymes from other sources. 12-lipoxygenase activity was detected in homogenates of human and dog gingiva after 2 min incubation with exogenous arachidonic acid. 12-HETE was the major metabolite in both species. The 12-lipoxygenase activity in homogenates of human gingiva and in platelets was inhibited by EDTA; it recovered after the addition of a divalent cation such as Ca2+. Its activity in dog gingiva and platelets was not affected by the chelator. Gingival 12-lipoxygenase, unlike platelet 12-lipoxygenase, was inhibited by AA861, a possible 5-lipoxygenase inhibitor. These findings suggest that gingival tissue has high levels of 12-lipoxygenase activity, but the enzyme in human gingiva differs from that in the dog in its dependency upon divalent cations, and gingival 12-lipoxygenase differs from the same enzyme in platelets in its sensitivity to an inhibitor.
Tamai
K
K
Department of Endodontology & Periodontology, Hiroshima University School of Dentistry, Japan.
Dohi
T
T
Ogawa
T
T
Okamoto
H
H
Tsujimoto
A
A
D019377:12-Hydroxy-5,8,10,14-eicosatetraenoic Acid; D000328:Adult; D000818:Animals; D001092:Arachidonate 12-Lipoxygenase / Q000737:chemistry* / Q000378:metabolism; D016718:Arachidonic Acid; D001095:Arachidonic Acids / Q000378:metabolism; D001345:Autoradiography; D016227:Benzoquinones / Q000494:pharmacology; D001792:Blood Platelets / Q000201:enzymology; D002118:Calcium / Q000494:pharmacology; D002855:Chromatography, Thin Layer; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism; D004285:Dogs; D004492:Edetic Acid / Q000494:pharmacology; D005881:Gingiva / Q000201:enzymology*; D006801:Humans; D006893:Hydroxyeicosatetraenoic Acids / Q000096:biosynthesis; D016859:Lipoxygenase Inhibitors; D008875:Middle Aged; D009504:Neutrophils / Q000201:enzymology
D001095:Arachidonic Acids; D016227:Benzoquinones; D006893:Hydroxyeicosatetraenoic Acids; D016859:Lipoxygenase Inhibitors; D016718:Arachidonic Acid; D019377:12-Hydroxy-5,8,10,14-eicosatetraenoic Acid; C036837:2,3,5-trimethyl-6-(12-hydroxy-5,10-dodecadiynyl)-1,4-benzoquinone; D003577:Cytochrome P-450 Enzyme System; D004492:Edetic Acid; D001092:Arachidonate 12-Lipoxygenase; D002118:Calcium