Korean J Phys Anthropol.  2011 Sep;24(3):175-183.

Expression of Tissue Inhibitors of Metalloproteinases in Developing Rat Tooth Germs

• Moon YH
• Kang JH
• Jeong NJ
• Ko HM
• Lee EJ
• Kim SH
• Kim MS

Abstract

Tissue inhibitors of metalloproteinases (TIMPs) are a family of secreted molecules that were identified as natural inhibitors of matrix metalloproteinases (MMPs). Tooth histomorphogenesis and cytodifferentiation are accompanied by rapid changes in cellular organization and remodeling of the extracellular matrix, in which MMPs and TIMPs might be expected to play significant roles. This study examined the expression and localization of TIMP-1 and TIMP-2 during the molar development of rats. The expression patterns of TIMPs were determined from Sprague-Dawley rat pups including the developing molars using RT-PCR, western blot and immunofluorescent staining. Gene and protein quantification analyses showed that both TIMPs increased from the cap stage to the root stage tooth germs. In contrast, the immunofluorescent data showed that they were expressed slight differentially. TIMP-1 was strongly expressed in secretory ameloblasts and moderate immunoreactivity was observed along the basement membrane. TIMP-2 expression was also detected in the basement membrane. Although strong immunoreactivity was observed in the secretory ameloblasts and enamel matrix itself, differentiated odontoblasts showed weak reactivity. However, little reactivity for both TIMPs were detected in the cap stage tooth germs and surrounding tissues. These distinct temporospatial expression patterns of TIMPs suggest that the TIMPs may play a variety of roles including dental hard tissue formation during molar tooth development.

Keyword

MMP; TIMP; Tooth development

MeSH Terms

Ameloblasts
Animals
Basement Membrane
Blotting, Western
Dental Enamel
Extracellular Matrix
Humans
Matrix Metalloproteinases
Metalloproteases
Molar
Odontoblasts
Rats
Tissue Inhibitor of Metalloproteinase-1
Tissue Inhibitor of Metalloproteinase-2
Tooth
Tooth Germ
Matrix Metalloproteinases
Metalloproteases
Tissue Inhibitor of Metalloproteinase-1
Tissue Inhibitor of Metalloproteinase-2