Chadha Sandeep, Jain Vanita, Gupta Indu, Khullar Madhu
Department of Obstetrics and Gynecology, Department of Experimental Medicine, Post-Graduate Institute of Medical Education and Research, Chandigarh, India.
J Obstet Gynaecol Res. 2007 Oct;33(5):710-7. doi: 10.1111/j.1447-0756.2007.00639.x.
To investigate the role of nitric oxide metabolites as markers of infection in subjects with preterm labor or preterm premature rupture of membranes (PTPROM). PTPROM means that there was spontaneous rupture of fetal membrane before the onset of labor and gestational age was <37 weeks. This occurs because of imbalance between matrix metalloproteinase and tissue inhibitor of matrix metalloproteinase. The cause of this imbalance that leads to degradation of collagen causing PTPROM is infection. The bactericidal, fungicidal, viricidal and tumoricidal activities of macrophages are determined in part by elaboration of nitric oxide, hence nitric oxide levels have been found to be increased in infections.
During an 18-month period 50 women with preterm labor or PTPROM and 50 controls were enrolled prospectively. Blood and urine samples were obtained for analysis of nitric oxide metabolites. Patients with known causes of preterm labor were excluded.
The nitric oxide metabolites, which included both nitrite levels and citrulline levels were significantly higher both in blood as well as urine in patients with preterm labor and PTPROM compared to controls. Serum nitrite levels in subjects with preterm labor were 376.5 +/- 345 nmol/L while in subjects with PTPROM they were 295.7 +/- 161.1 nmol/L and in controls the levels were 62.7 +/- 33.9 nmol/L. Serum citrulline levels in subjects with preterm labor were 5293.8 +/- 2916.7 nmol/L; in PTPROM they were 6536.6 +/- 609.91 nmol/L and in controls they were 949.8 +/- 67.1 nmol/L. On comparing patients with preterm labor, those in whom preterm labor could not be inhibited had statistically significant higher levels of nitrite in both serum and urine (482.9 +/- 387.7 nmol/L and 754.5 +/- 336.5 nmol/L, respectively) compared to patients in whom labor could be inhibited (172.2 +/- 61.9 nmol/L and 401.8 +/- 236.9 nmol/L, respectively). The citrulline levels were also higher among the group who delivered preterm for both serum and urine (5355.4 +/- 3229.7 nmol/L and 11 482.8 +/- 2541.4 nmol/L, respectively) compared to patients in whom labor could be inhibited (5260.2 +/- 2897.08 nmol/L and 10 651.4 +/- 1502.7 nmol/L, respectively) but this did not reach statistical significance.
Higher nitric oxide metabolites in women with preterm labor are marker of subclinical infection.
研究一氧化氮代谢产物作为早产或胎膜早破（PTPROM）患者感染标志物的作用。PTPROM是指在临产前胎膜自发破裂且孕周小于37周。这是由于基质金属蛋白酶与基质金属蛋白酶组织抑制剂之间失衡所致。导致胶原蛋白降解从而引起PTPROM的这种失衡的原因是感染。巨噬细胞的杀菌、杀真菌、杀病毒和杀肿瘤活性部分由一氧化氮的产生所决定，因此已发现感染时一氧化氮水平会升高。
在18个月期间，前瞻性纳入了50例早产或PTPROM患者以及50例对照。采集血液和尿液样本以分析一氧化氮代谢产物。排除已知早产原因的患者。
与对照组相比，早产和PTPROM患者血液和尿液中的一氧化氮代谢产物，包括亚硝酸盐水平和瓜氨酸水平均显著更高。早产患者的血清亚硝酸盐水平为376.5±345 nmol/L，PTPROM患者为295.7±161.1 nmol/L，对照组为62.7±33.9 nmol/L。早产患者的血清瓜氨酸水平为5293.8±2916.7 nmol/L；PTPROM患者为6536.6±609.91 nmol/L，对照组为949.8±67.1 nmol/L。与能够抑制宫缩的患者相比，无法抑制宫缩的早产患者血清和尿液中的亚硝酸盐水平在统计学上显著更高（分别为482.9±387.7 nmol/L和754.5±336.5 nmol/L）（能够抑制宫缩的患者分别为172.2±61.9 nmol/L和401.8±236.9 nmol/L）。早产组患者血清和尿液中的瓜氨酸水平也更高（分别为5355.4±3229.7 nmol/L和11482.8±2541.4 nmol/L），而能够抑制宫缩的患者分别为5260.2±2897.08 nmol/L和10651.4±1502.7 nmol/L，但这未达到统计学显著性。
早产女性中较高的一氧化氮代谢产物是亚临床感染的标志物。
