| Accession number;02A0151474 |
| Title;Effects of Nitric Oxide (NO)-Donor and -Scavenger on Contractile Responses in Isolated Fetal Sheep Carotid and Renal Arteries. |
| Author;ANZAI KEN(Fukushimaken'idai I Sanfujinka) OKAWA TOSHIAKI(Fukushimaken'idai I Sanfujinka) HONDA SHIN'YA(Fukushimaken'idai I Sanfujinka) SAMPEI MINORU(Fukushimaken'idai I Sanfujinka) FUJIMORI KEIYA(Fukushimaken'idai I Sanfujinka) YANAGIDA KAORU(Fukushimaken'idai I Sanfujinka) SATO AKIRA(Fukushimaken'idai I Sanfujinka) |
Journal Title;Acta Obstetrica et Gynaecologica Japonica
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Journal Code:F0923A
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ISSN:0300-9165
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VOL.54;NO.1;PAGE.10-16(2002)
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| Figure&Table&Reference;FIG.6, REF.21 |
| Pub. Country;Japan |
| Language;Japanese |
| Abstract;Objective: The aim of this study was to illuminate the mechanism of a redistribution of blood flow in fetuses. Nitric oxide is now known to play important functional roles in the vasculature. We measured plasma nitrate (the metabolites of nitric oxide) concentrations in maternal and fetal sheep at term, and compared the effect of NO donors on isolated carotid and renal arteries from fetuses. Methods: (1) Blood samples were taken from maternal and fetal arteries in sheep at 132 .+-. 2 day's gestation, and were collected for nitrate determination with Griess reagent. (2) Rings of carotid and renal arteries with intact endothelium from fetal sheep were positioned in organ chambers filled with Krebs-Henseleit solution (37.DEG.C.) bubbled with 5% CO2 in air (pH: 7.4) and isometric tension was recorded. Concentration-response relationships to sodium nitroprusside (SNP), nitroglycerine (NTG) and diethylamine nitric oxide (DEA/NO) with pretreatment NO scavenger, oxyhemoglobin (10-5 M), and vehicle were determined. Results: (1) Plasma nitrate levels were significantly higher in fetuses than in maternal sheep. (2) Nitric oxide donor concentrations dependently inhibited in phenylepherine-precontracted carotid and renal arteries. The relaxation of both rings was attenuated by previous treatment with oxyhemoglobin. Nitric oxide sensitivity was greater in carotid arteries than in renal arteries. The order of potency was SNP > NTG> DEA/NO in the two types of arteries. Conclusion: These observations indicate that NO may play an important role in the redistribution of blood flow in fetuses. (author abst.) |
