In vitro and in vivo studies of osteoclasts by effect of EGF or PGE_2
| Project/Area Number |
62570807
|
|---|
| Research Category |
Grant-in-Aid for General Scientific Research (C)
|
| Allocation Type | Single-year Grants |
|---|
| Research Field |
Morphological basic dentistry
|
|---|
| Research Institution | Kyushu University (1988)
福井医科大学 (1987) |
|---|
Principal Investigator |
TANAKA Teruo First Department of Oral Anatomy, Faculty of Dentistry, Prof., 歯学部, 教授 (60077667)
|
|---|
| Project Period (FY) |
1987 – 1988
|
| Project Status |
Completed (Fiscal Year 1988)
|
| Budget Amount *help |
¥2,200,000 (Direct Cost: ¥2,200,000)
Fiscal Year 1988: ¥800,000 (Direct Cost: ¥800,000)
Fiscal Year 1987: ¥1,400,000 (Direct Cost: ¥1,400,000)
|
|---|
| Keywords | EGF / PGE_2 / Osteoclasts / In vitro study / In vivoの研究 / in vitroの研究 / PGE2 / in vitro / in vivo |
|---|
| Research Abstract |
Rats after injection of EGF or PGE2 or after 6 day tooth movement ( Waldo method ) were investigated by intravenous injection of microper-oxidase ( MP, peptide tracer ) or by tatrate-resistant acid phospha-tase(TRAP) staining. Bone resorption was observed at a distal bone surface of the interradicular septum of the upper first molar tooth, and tooth root resorption was found along mesial and distal root surfaces of the distal root of the above tooth. Odontoclasts had the same organellae ( multinuclear, well-developed ruffled border(RB), clear zone, vaculoes, mitochondria and specific granules ) that osteo-clasts possess. The clear zone did not stop any MP, therefore the MP deposited on the resorbed area through the clear zone and was transported into the vacuoles only along the channels of the RB. In addition, collagen fibrils localized in the channels of the RB but were not detected in the vacuoles. Instead, filament-like structures were detected in the vacuoles and were locating very near the collagen fibrils in the channels. Fibroblasts out of the resorbed lacunae endocytosed collagen. In contrast, the fibroblasts together with odontoclasts in the lacunae did not endocytose any collagen fibrils. It was also characteristic that little cellular uptake of MP by odontoclasts was observed, compared with that by osteoclasts.
These findings suggested, first that odontoclasts resorb the dentin ( cementum ) of the tooth roots, just as osteoclasts do in bone resorption, second that the resorbed area connects with the extracellular spaces without sealing off by the clear zone, and third that the organic components( ex. collagen fibrils ) of dentin or cementum are endocytosed through the channels of the RB in the same endocytotic manner as that for MP, although the endocytotic ability of odontoclasts is inferior to that of osteoclasts.
|
Report
(3 results)
Research Products
(9 results)
