潰瘍性大腸炎とクローン病における酸化窒素合成酵素の活性
N K Boughton-Smith1, S M Evans, C J Hawkey
1Wellcome Research Laboratories, Beckenham, Kent, UK.
Lancet (London, England)
|August 7, 1993
まとめ
結腸内粘膜における酸化窒素 (NO) 合成酵素の活性が高まっていることは,潰瘍性大腸炎と関連しているが,クローン病とは関係ありません. この発見は,活性性潰瘍性大腸炎の炎症および潜在的な運動性の問題におけるNOの役割を示唆しています.
科学分野:
- 胃腸内科 胃腸内科
- 分子生物学は分子生物学である.
- 免疫学 免疫学とは
背景:
- 炎症的刺激は窒素酸化物 (NO) 合成酵素を誘発し,NOの過剰生産につながる可能性があります.
- 過剰なNOは,血管の透過性の変化と組織損傷に寄与する.
- 炎症性腸疾患におけるNO合成酵素の活動は完全に理解されていません.
研究 の 目的:
- 潰瘍性大腸炎およびクローン病の患者の結腸内粘膜および筋肉におけるNO合成酵素の活性を測定し,対照群と比較する.
- 潰瘍性大腸炎とクローン病の病理生理学におけるNO合成酵素誘導の潜在的な役割を調査する.
主な方法:
- NO合成酵素の活動は,大腸の粘膜組織と筋肉組織で測定されました.
- サンプルは,対照患者,潰瘍性大腸炎患者,クローン病患者から採取された.
- グループ間の酵素活性を比較するために,統計分析が行われました.
主要な成果:
- NO合成酵素の活性度は,対照群と比較して,潰瘍性大腸炎患者の大腸内粘膜で約8倍高かった (p < 0.001).
- NO合成酵素の活性における有意な違いは,潰瘍性大腸炎患者の結腸筋や,対照群と比較してクローン病患者の組織では観察されなかった.
- クローン病患者の粘液中のNO合成酵素の活性度は,対照値と異なるものではありません.
結論:
- 粘膜における大腸 NO 合成酵素の誘導は,粘膜の血管拡張と,活発な潰瘍性大腸炎の特徴である血管浸透性の増加に関与しています.
- NO合成酵素の活性度の上昇は,潰瘍性大腸炎に関連した有毒膨張で観察される運動障害にも寄与する可能性があります.
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