Project/Area Number |
63570150
|
Research Category |
Grant-in-Aid for General Scientific Research (C)
|
Allocation Type | Single-year Grants |
Research Field |
Human pathology
|
Research Institution | Tokai Univ, School of Medicine |
Principal Investigator |
KAKUDO K. Tokai Univ. Dept of Pathol. Assist. Prof., 医学部・病理学, 講師 (00112037)
|
Co-Investigator(Kenkyū-buntansha) |
OSAMURA Y. Tokai Univ. Dept of Pathol. Prof., 医学部・病理学, 教授 (10100992)
WATANABE K. Tokai Univ. Dept of Pathol. Prof., 医学部・病理学, 教授 (00055865)
|
Project Period (FY) |
1988 – 1989
|
Project Status |
Completed (Fiscal Year 1989)
|
Budget Amount *help |
¥400,000 (Direct Cost: ¥400,000)
Fiscal Year 1989: ¥400,000 (Direct Cost: ¥400,000)
|
Keywords | Thyroid Gland / C cell / Calcitonin / Secretion / Cell cycle / Calcium metabolism / GCRP / カルシトニン遺伝子関連ペプチド / 細胞内プロセシング / 遺伝子プロセシング |
Research Abstract |
Calcitonin(CT) and calcitonin gene-related peptide(CGRP) are synthesized in and secreted from the C cells of the thyroid. To study regulation mechanism of these peptides, the following studies were carried out and clarified. These 2 peptides are localized in the neurosecretory granules of the human C cells of the thyroid at electron microscopic level. When calcium channel blocker nifedipine was applied on cultured C cells(TT cells), CT secretion in the culture media was reduced and numbers of secretory granules in the TT cells were increased. When synthetic salmon calcitonin (TZ-CT) was injected in rats, tissue CT contents reduced in thyroid markedly. In addition to it, CT-m-RNA in the thyroid dropped at 50-80%. Thus TZ-CT administration suppresses CT-m-RNA translation and CT synthesis. Long term TZ-CT administration in the rats suppressed C cell population in the rats thyroid. This negative feedback mechanism may suggests that C cells may have CT receptors and were regulated CT synthesis and secretion by serum CT levels directly rather than by serum calcium level indirectly.
|