Cook M N, Nakatsu K, Marks G S, McLaughlin B E, Vreman H J, Stevenson D K, Brien J F
Department of Pharmacology and Toxicology, Faculty of Medicine, Queen's University, Kingston, ON, Canada.
Can J Physiol Pharmacol. 1995 Apr;73(4):515-8. doi: 10.1139/y95-065.
Rat aorta was homogenized and the 13000 x g supernatant fraction was tested for heme oxygenase (HO) activity by using a sensitive gas chromatographic method to measure carbon monoxide (CO), one of the products of the HO reaction. The rate of NADPH-dependent CO formation, an index of HO activity, was 1.41 +/- 0.40 nmol CO.mg(-1)protein. h(-1) in the rat aorta supernatant fraction and 2.05 +/- 0.55 nmol CO.mg(-1) protein.h(-1) in the rat liver 13000 x g supernatant fraction, a tissue known to contain HO activity. Chromium mesoporphyrin (0.05 mM), an inhibitor of rat liver HO, significantly decreased HO activity by 26% in the aorta supernatant fraction and 50% in the liver supernatant fraction. On the basis of the results of this study, which demonstrated HO-catalyzed CO formation in aortic tissue, and previous observations that CO relaxes vascular smooth muscle, we suggest that a physiological role for CO in vascular smooth muscle relaxation should be further investigated.
将大鼠主动脉匀浆，通过使用灵敏的气相色谱法测量血红素加氧酶（HO）反应产物之一一氧化碳（CO），来检测13000×g上清液部分的血红素加氧酶（HO）活性。作为HO活性指标的NADPH依赖性CO生成速率，在大鼠主动脉上清液部分为1.41±0.40 nmol CO·mg⁻¹蛋白质·h⁻¹，在已知含有HO活性的大鼠肝脏13000×g上清液部分为2.05±0.55 nmol CO·mg⁻¹蛋白质·h⁻¹。大鼠肝脏HO抑制剂中卟啉铬（0.05 mM）可使主动脉上清液部分的HO活性显著降低26%，使肝脏上清液部分的HO活性显著降低50%。基于本研究结果（该结果证明了主动脉组织中存在HO催化的CO生成）以及之前关于CO可使血管平滑肌舒张的观察结果，我们认为应进一步研究CO在血管平滑肌舒张中的生理作用。
