CONTRIBUTION OF NITRIC OXIDE RELEASED TO METABOLIC VASODILATION IN THE HEART

血管的内层(内皮)释放的物质会导致 衬里下面的平滑肌肉的松弛。放松 对于维持正常的血管张力是必不可少的 从而控制血液流动。硝酸盐释放不足 氧化物会导致血管的不适当扩张，从而 血流受限程度增加。来考察放松政策是否 伴随着心率加快的时期的血管， 我们研究了L-NMMA对血管紧张素转换酶释放的抑制作用。 一氧化氮对快速起搏产生的血流量增加的影响 心。正常情况下，给心脏起搏会增加33%的血流量， 但在阻止一氧化氮的释放后，这一比例降至9% 与L-NMMA。这表明从衬里释放的一氧化氮 心脏中血管的运动对松弛动脉很重要，因此 控制心脏的血液流动。导致以下情况的条件 心脏内层功能的异常可能通过 减少血流量，导致心绞痛加重。

The lining of blood vessels (endothelium) releases substances that cause relaxation of smooth muscle that underlies the lining. The relaxation of the smooth muscle is essential in maintaining normal blood vessel tone and thus the control of blood flow. Deficiency in the release of nitric oxide would lead to inappropriate dilation of blood vessels and thus to limitation of the blood flow increase. To examine whether the relaxation of blood vessels that accompanies periods when the heart rate increases, we studied the effect of L-NMMA, which is an inhibitor of release of nitric oxide, on the blood flow increase produced by rapidly pacing the heart. Normally, pacing the heart produces a 33% increase in blood flow, but this was reduced to 9% after blocking the release of nitric oxide with L-NMMA. This suggests that release of nitric oxide from the lining of blood vessels in the heart is important in relaxing arteries and thus controlling blood flow in the heart. Conditions that lead to abnormalities of the function of the lining of the heart could, by reducing blood flow, lead to worsening of angina.