Budget Amount *help |
¥2,100,000 (Direct Cost: ¥2,100,000)
Fiscal Year 1996: ¥800,000 (Direct Cost: ¥800,000)
Fiscal Year 1995: ¥1,300,000 (Direct Cost: ¥1,300,000)
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Research Abstract |
Purpose : Fetal wound rapidly heals without leukocytes invasion and scar formation, as opposed to adult wound. Recent studies have shown that nitric oxide (NO) exerts biolo-gic activities potentially relevant to tissue repair, including microbiostasis, leukocyte adhesion to endothelium, micro-vascular permeability, angiogenesis, vasodilation and inhi-bition /reversal of platelet aggregation. There are possibilities that NO production in fetal wound differs from that in adult wound. However, no reports have evidenced NO production in wound. The aim of this study was the first to determine the above hypothesis. Methods : Adult pregnant New Zealand White rabbits were used. Seated polyvinylalcohol sponge measuring 1.5*0.8cm was implanted subcutaneously in the dorsum of the fetus (24 days of gestation). Thenafter, pregnancy was continued. In a way, adult nonpregnant rabbits were used as control. Seated polyvinylalcohol sponge measuring 2.5*1.2cm was implanted subcutaneously in their dorsum. In both groups, the sponges were harvested at 1 to 7 days after implantation. Wound fluid was obtained from the sponge, centrifuged and the concentration of nitrite+nitrate was measured with Greiss reaction. Moreover, spieces consisting of the wound with sponge were stained with NADPH diaphorase by histochemical method. Results : In adult, nitrite+nitrate significantly increased at 2nd day of implantation and then gradually decreased. In fetus, nitrite+nitrate significantly increased at 2nd and 5th day as compared to the other days, and these concentrations were significantly higher than that in adult wound. Some of macrophages in the sponge within fetal wound at 5-days of implantation were stained positive to NADPH diaphorase. Conclusions : These results implicated that NO production is induced in both adult and fetal wound, but difference was noted in NO levels and peak patterns between them. NO would play an important role in regulating the above events characteristic within wound.
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