| Project/Area Number |
05670671
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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 |
Pediatrics
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| Research Institution | Shiga University of Medical Science |
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Principal Investigator |
NAKAGAWA Masao SUMS,Dept of Ped.Ass.Prof., 医学部, 講師 (40188909)
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| Co-Investigator(Kenkyū-buntansha) |
KURIBAYASHI Toshiro KPUM,Dept of 2nd Anatomy, Ass.Prof., 医学部, 講師 (80186519)
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| Project Period (FY) |
1993 – 1994
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| Project Status |
Completed (Fiscal Year 1994)
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| Budget Amount *help |
¥2,100,000 (Direct Cost: ¥2,100,000)
Fiscal Year 1994: ¥1,400,000 (Direct Cost: ¥1,400,000)
Fiscal Year 1993: ¥700,000 (Direct Cost: ¥700,000)
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| Keywords | Whole embryo culture / Sixth aortic arch / HNK-1 / N-CAM / WKY / NCrj rat / Neural crest cell / cardiac anomaly / N-CAM |
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| Research Abstract |
1.Morphological analysis of the heart in WKY/NCrj and control rat embryos raised in whole embryo culture.
1) Sixth aortic arches were detected in both WKY/NCrj and control rat embryos cultured for 12 hours from 11.5 days of gestation. No morphological differences of the sixth aortic arches were observed between these two strains of embryos during 48 hours of culture.
2) As the embryos cultured over 48 hours showed developmental delay compared with age-matched controls, this whole embryo culture system appeared useful only when performed for 48 hours.
2.Immunolocalizations of extracellular molecules including migrating neural crest cell markers in the heart of WKY/NCrj and control rat embryos.
HNK-1, N-CAM,fibronectine and cytotactin were immunopositive in the sixth aortic arches of both WKY/NCrj and control rat embryos at 11.5,12.5 and 13.5 day of gestation. The distributional patterns of those markers were almost same between WKY/NCrj and control rat embryos. N-CAM showed a chain of immunopositive tissues from nerve fibers around the foregut to the truncus arteriosus via the sixth aortic arch, which indicated that the sixth aortic arch was one of the pathways neural crest cells migrate through from splanchnic mesenchymal tissues to the truncus arteriosus. However, this study also suggested that cardiac malformations in WKY/NCrj rat might not be induced by hypoplastic sixth aortic arches or abnormal migrations of neural crest cells through this pathway.
Conclusively, the hypoplastic sixth aortic arches in WKY/NCrj rat embryos at 14.5 day of gestation were supposed to be secondarily brought by an abnormal truncal division. Therefore, we are planning to clarify the distributional patterns or migratory pathways of cardiac neural crest cells which may play an important role in truncal division.
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