| Project/Area Number |
06839010
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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 |
海洋生物学
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| Research Institution | UNIVERSITY OF TOKYO |
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Principal Investigator |
KANEKO Toyoji UNIV.TOKYO,OCEAN RES.INST., ASSIST.PROF., 海洋研究所, 助手 (70221190)
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| Project Period (FY) |
1994 – 1995
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| Project Status |
Completed (Fiscal Year 1995)
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| Budget Amount *help |
¥2,000,000 (Direct Cost: ¥2,000,000)
Fiscal Year 1995: ¥800,000 (Direct Cost: ¥800,000)
Fiscal Year 1994: ¥1,200,000 (Direct Cost: ¥1,200,000)
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| Keywords | Chloride cell / Yolk sac membrane / Osmoregulation / Chum salmon / Tilapia / 卵黄のう上皮 / 発眼卵 |
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| Research Abstract |
The present study was undertaken to clarify the osmoregulatory mechanisms during early life stages in fish and to investigate the possible involvement of chloride cells in the yolk-sac membrane in osmoregulation, using euryhaline tilapia (Oreochromis mossambicus) and chum salmon (Oncorhynchus keta). The followings are the results obtained for the last two years :
1.Eyed-stage embryos of chum salmon possess hypoosmoregulatory ability and chloride cells in the yolk-sac membrane may be involved in salt extrusion, in place of gill chloride cells, during the late embryonic stages.
2.Similarly, in tilapia embryos, chloride cells in the yolk-sac membrane are potentially important sites for ion exchange in seawater.
3.In tilapia, cortisol treatment stimulates the size and number of chloride cells in the yolk-sac membrane of embryos and larvae in vivo and in vitro, suggesting that cortisol present in the yolk may be involved in osmoregulation during early life stages.
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