| Project/Area Number |
10671708
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (C)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
Morphological basic dentistry
|
|---|
| Research Institution | Iwate Medical University |
|---|
Principal Investigator |
TACHIBANA Tamiko IWATE MEDICAL UNIVERSITY, ORAL ANATOMY II, ASSOCIATE PROFESSOR, 歯学部, 助教授 (10089386)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
FUJIWARA Naoki IWATE MEDICAL UNIVERSITY, ORAL ANATOMY II, TEACHING FELLOW, 歯学部, 助手 (20190100)
|
|---|
| Project Period (FY) |
1998 – 1999
|
| Project Status |
Completed (Fiscal Year 1999)
|
| Budget Amount *help |
¥3,300,000 (Direct Cost: ¥3,300,000)
Fiscal Year 1999: ¥1,100,000 (Direct Cost: ¥1,100,000)
Fiscal Year 1998: ¥2,200,000 (Direct Cost: ¥2,200,000)
|
|---|
| Keywords | MERKEL CELL / CELL DIFFERENTIATION / CELL PROLIFERATION / APOPTOSIS / PALATINE MUCOSA / PERIPHERAL NERVE DEVELOPMENT / 細胞分裂能 / Ki67 / Waf1 / サイトケラチン |
|---|
| Research Abstract |
TO ELUCIDATE THE LIFE SPAN AND LIFE CYCLE OF MERKEL CELLS, DIFFERENTIATION AND POTENTIALS OF MITOSIS AND APOPTOSIS OF MERKEL CELLS WERE STUDIED BY IMMUNOHISTOCHEMISTRY USING DEVELOPING AND GROWING PALATINE MUCOSAE OF RATS. IMMUNOHISTOCHEMISTRY FOR CYTOKERATIN 18 SHOWED THAT MERKEL CELLS IN THE RAT PALATINE MUCOSA EMERGE AFTER BIRTH IN CONTRAST TO SIMILAR CELLS IN THE SKIN IN WHICH THE CELLS DIFFERENTIATE DURING THE EMBRYONIC PERIOD. IT WAS FOUND THAT THE MERKEL CELLS IN THE RAT PALATINE MUCOSA INCREASED IN NUMBER TO MAXIMUM BY THE END OF THE FIRST POSTNATAL MONTH. THERE WERE NO MERKEL CELLS IN THE LAMINA PROPRIA OF THE PALATINE MUCOSA DURING THE CELL INCREASE PERIOD. HOWEVER, NO MERKEL CELLS SHOWED POSITIVE IMMUNOREACTION FOR ANTI-K167 ANTIBODY, A RELIABLE MARKER FOR MITOTIC NUCLEI, DURING THE CELL INCREASE PERIOD. ALL MERKEL CELLS SHOWED A STRONG AFFINITY FOR ANTI-P27 ANTIBODY, A CYCLINE D-KINASE INHIBITOR. THESE RESULTS SUGGEST MERKEL CELLS INCREASE IN NUMBER BY DIFFERENTIATION FROM EPITHELIAL STEM CELLS, BUT NOT BY MITOSIS OF ALREADY DIFFERENTIATED CELLS.
IT WAS ALSO FOUND THAT MERKEL CELLS lN THE POSTERIOR HARD PALATE OF THE RAT DRASTICALLY DECREASED IN NUMBER DURING ITS PREMATURE TO MATURE PERIOD. NO MERKEL CELLS SHOWED POSITIVE REACTIONS FOR A NICK END LABELING, A METHOD FOR DETECTING APOPTOSIS. IN CONTRAST, THERE WERE MANY MERKEL CELLS IN THE SURFACE EPITHELIAL LAYERS OF THE RAT POSTERIOR HARD PALATE OF THE PREMATURE PERIOD, SUGGESTING DROPPING OUT OF THESE CELLS. THESE RESULTS INDICATE THAT DECREASE IN NUMBER OF MERKEL CELLS IS ACHIEVED BY DESQUAMATION BUT NOT APOPTOSIS.
IN CONCLUSION, THE PRESENT STUDY SHOWED THAT MERKEL CELLS IN NORMAL DEVELOPING AND GROWING ORAL MUCOSA HAVE NO POTENTIAL OF MITOSIS NOR APOPTOSIS.
|
