title: Evidence of gelatinase secretion by the submandibular gland in prepubescent rats.
abstract: The gelatin cleaving activities in secretions of cultured fragments of male rat submandibular glands were studied using zymography. Gelatinolytic activities of 88-, 64-, and 57-kDa proteins detected in the tissues from 22-28-day old animals were undetectable in 31-70-day old rats. The traces of gelatinolytic activity associated with 28-kDa protein were detectable from 22-day old rats in serum-free media, and this activity of the enzyme markedly increased with aging from 38-days old. At 52-days and the subsequent stages, in addition to 28-kDa, activities associated with 60-, 32-, and 29-kDa proteins were strong. When the conditioned media were treated with 1,10-phenanthroline and diisopropyl fluorophosphate (DFP), both products inhibited activity of 88-kDa enzyme, indicating that this enzyme is Cls-like enzyme. The 64- and 57-kDa activities were inhibited by 1,10-phemanthroline, but not by DFP; when the conditioned medium of the tissue from 24-day old rats was treated with p-aminophenylmercuric acetate, gelatinolytic activity associated with 64-kDa converted to 57-kDa. Therefore, 64- and 57-kDa activities were concluded to be progelatinase A and gelatinase A, respectively. On the other hand, the gelatinolytic activities associated with 60-, 32-, 29- and 28-kDa proteins were inhibited by DFP but not by 1,10-phenanthroline, indicating that these enzymes belong to the family of serine proteinase, most probably kallikrein-related enzymes. From these findings, it was suggested that gelatinase A, along with Cls-like enzyme, participates in the maturation of the submandibular gland before it becomes active as an exocrine organ.
authors.affiliation: Department of Biochemistry, Kanagawa Dental College, Yokosuka, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Kato
authors.forename: S
authors.initials: S
authors.lastname: Ozono
authors.forename: S
authors.initials: S
authors.lastname: Koshika
mesh_terms: D000375:Aging / Q000502:physiology; D000818:Animals; D018929:Cell Culture Techniques; D002454:Cell Differentiation / Q000187:drug effects / Q000502:physiology*; D017077:Culture Media, Conditioned / Q000494:pharmacology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D004792:Enzyme Precursors / Q000037:antagonists & inhibitors / Q000378:metabolism; D004847:Epithelial Cells / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism*; D018093:Gelatinases / Q000037:antagonists & inhibitors / Q000378:metabolism; D007527:Isoenzymes / Q000037:antagonists & inhibitors / Q000378:metabolism; D008297:Male; D020778:Matrix Metalloproteinase 2 / Q000378:metabolism*; D061965:Matrix Metalloproteinase Inhibitors; D008666:Metalloendopeptidases / Q000037:antagonists & inhibitors / Q000378:metabolism; D008970:Molecular Weight; D051381:Rats; D011916:Rats, Inbred F344; D012697:Serine Endopeptidases / Q000378:metabolism; D012741:Sexual Maturation / Q000502:physiology; D013363:Submandibular Gland / Q000201:enzymology / Q000254:growth & development* / Q000378:metabolism*
chemical_list: D017077:Culture Media, Conditioned; D004791:Enzyme Inhibitors; D004792:Enzyme Precursors; D007527:Isoenzymes; D061965:Matrix Metalloproteinase Inhibitors; D012697:Serine Endopeptidases; D018093:Gelatinases; D008666:Metalloendopeptidases; C069860:progelatinase; D020778:Matrix Metalloproteinase 2