2001 Fiscal Year Final Research Report Summary
Expression of CRF and iNOS mRNA in the hypothalamus and the mode of response to stress.
Project/Area Number |
11671657
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Research Category |
Grant-in-Aid for Scientific Research (C)
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Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
Obstetrics and gynecology
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Research Institution | Nippon Medical School |
Principal Investigator |
AKIRA Shigeo Nippon Medical School, Dept.of OB/GYN, Associate Professor, 医学部, 助教授 (40231849)
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Co-Investigator(Kenkyū-buntansha) |
IMAKI Junko Nippon Medical School, Dept.of Anatomy 1, Assistant Professor, 医学部, 講師 (20223323)
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Project Period (FY) |
1999 – 2001
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Keywords | CRF / iNOS / rat / fetus / LPS / in situ hybridization |
Research Abstract |
We investigated the expression of CRF and iNOS mRNA, and the mode of response to lipopolysaccharide (LPS) loading in rat embryo models for infection. Embryos were delivered by cesarean section at day 20 of pregnancy and immediately placed in a chamber with the temperature controlled at 37℃ and the humidity at 100%. Either LPS (400μg/100g of the body weight) or physiological saline was administered to embryos, and the embryos were maintained for 3 hours. Embryos were decapitated after cesarean section and after 3 hours of maintenance. Fetal brain was collected, fixed, and prepared by coronal section. We produced a ^<35>S-UTP-labelled antisense RNA probe for CRF and iNOS, and performed in situ hybridization. The expression of CRF and iNOS was analyzed by optical density. Moreover, blood corticosterone was assayed by radioimmunoassay. The expression of iNOSmRNA was not seen in the control group, but the expression was identified in the subfornical organs and the choroids plexus, although no expression was seen in the paraventricular nucleus in the LPS group. Significantly increased blood corticosterone was observed in the LPS group. In conclusion, in 20-day-old embryos, the CRF-ACTH-corticosterone pathway has been activated in response to the stress of LPS loading. However, the absence of expression of iNOSmRNA on the paraventricular nucleus suggests that NO is not the major stress-transmission mediator in stimulating CRF release in response to LPS loading.
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