| Project/Area Number |
04670219
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| Research Category |
Grant-in-Aid for General Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Research Field |
Experimental pathology
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| Research Institution | Osaka Medical College |
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Principal Investigator |
MORI Hiroshi OSAKA MEDICAL COLLEGE, DEPT.OF PATHOLOGY, PROFESSOR, 医学部, 教授 (40028519)
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| Co-Investigator(Kenkyū-buntansha) |
ITO Yasuhiro OSAKA MEDICAL COLLEGE, DEPT.OF PATHOLOGY, SENIOR INVESTIGATOR, 医学部, 助手 (10232480)
UENO Hiroshi OSAKA MEDICAL COLLEGE, DEPT.OF PATHOLOGY, SENIOR INVESTIGATOR, 医学部, 助手 (90142596)
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| Project Period (FY) |
1992 – 1993
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| Project Status |
Completed (Fiscal Year 1993)
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| Budget Amount *help |
¥2,000,000 (Direct Cost: ¥2,000,000)
Fiscal Year 1993: ¥500,000 (Direct Cost: ¥500,000)
Fiscal Year 1992: ¥1,500,000 (Direct Cost: ¥1,500,000)
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| Keywords | TESTICULAR LEYDIG CELL / STEM CELL / REGENERATION / RAT / ETHANE DIMETHANESULPHONATE / BROMODEOXYURIDINE / TESTOSTERONE / Ethanedimethanesulfonate / bromodeoxyuridine / ethanedimethanesulfonate |
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| Research Abstract |
To determine whether the proliferation of Leydig cells of testicular interstitial tissue comes from maturation of precursor cells or from division of stem cells, the regeneration of Leydig cells impaired by repeated administration of ethane dimethanesulphonate (EDS) was studied, mainly using morphometric analysis. Second injection of EDS (75 mg/kg BW, ip) with an interval of 30 days induced a similar event of disappearance and subsequent regeneration of Leydig cells as in the first EDS treatment with a fastened course of regeneration. Leydig cells reduced remarkably in number and volume percentage in the testicular tissue, and serum testosterone levels noticeably decreased within 2 days of 2nd EDS treatment. They began to reappear on 7 days, and recovered to the same extent as that in the control rats on 30 days, while they had began to reappear after 14 days of 1st EDS.Percentage of cells labeled by bromodeoxyuridine in the interstitial tissue increased remarkably on 2 days and returned to the level of control on 14 days. Repeated administration of EDS failed to deplete Leydig cells. On 30 days after 4th injection with an interval of respective 30 days, rats had almost the same number and total volume of Leydig cells and serum testosterone levels as in the control. These results strongly suggest that a stem cell for Leydig cells exists, and that the regeneration of Leydig cells occurs by division of the stem cells. EDS has been considered to impair specifically rat Leydig cells. However, the present study revealed that repeated treatments with EDS impair seminiferous tubules as well.
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