目的　为了研究血管内皮细胞合成分泌的血管活性物质一氧化氮（ Ｎ Ｏ） 在糖尿病人及血管并发症中的变化。方法　用高效液相色谱测定了７４ 例糖尿病病人和３０ 例正常人血浆 Ｎ Ｏ 水平，同时测定甲襞微循环血流及经颅多普勒血流。结果　（１） 糖尿病组血浆 Ｎ Ｏ 水平明显低于对照组〔（２ ２６８ ．６７ ±７８３ ．０３）ｎｇ／ｍｌ 对（２ ９２３ ．００ ±５４４ ．９１）ｎｇ／ ｍｌ， Ｐ＜ ０ ．０１〕；伴血管并发症的病人较无并发症的病人血浆 Ｎ Ｏ 水平亦有减低〔（２ １０１ ．０４ ±７８０ ．０８）ｎｇ／ ｍｌ 对（２ ７６７ ．５５ ±５９０ ．１５）ｎｇ／ｍｌ， Ｐ＜０ ．０１〕，随着血管并发症的增多，血浆 Ｎ Ｏ 的水平也随之降低。（２） 甲襞微循环总积分糖尿病组较对照组增高（ Ｐ＜ ０ ．０１） ；血流速度明显减慢（ Ｐ＜ ０ ．０１） 、颅底动脉血流速度明显高于对照组（ Ｐ＜ ０ ．０５ 或 Ｐ＜ ０ ．０１） 。（３） 糖尿病病人血浆 Ｎ Ｏ 与微循环血流速度呈直线正相关（ｒ ＝ ０ ．３０ ， Ｐ＜ ０ ．０１） ， Ｎ Ｏ 与颅底动脉血流速度呈负相关（ ｒ＝ － ０ ．７５ ，ｒ ＝ － ０ ．８９ ，ｒ ＝ － ０ ．８９ ， Ｐ＜ ０ ．０１） 。结论　说明 Ｎ Ｏ 在 Ｄ Objective To study the changes of nitric oxide (NO), a vasoactive substance synthesized and secreted by vascular endothelial cells, in patients with diabetes mellitus and vascular complications. Methods Plasma N 0 levels in 74 diabetic patients and 30 normal subjects were measured by high performance liquid chromatography (HPLC). The flow of nailfold microcirculation and transcranial Doppler were also measured. Results (1) The level of plasma N-O in diabetic group was significantly lower than that in the control group (2 268 .67 ± 783 .03) ng / ml vs (2 923 .00 ± 544 .91) ng / ml, P < 01]. Patients with vascular complications also had lower plasma N-O levels than those without complications (2 101 .04 ± 780 .08 ng / ml vs. (2767.555 ± 590.15) ng / ml , P <0. 01〕, with the increase of vascular complications, plasma N O levels also will be reduced. (2) The total score of nailfold microcirculation in diabetes mellitus group was higher than that in control group (P <0.01), the blood flow velocity was significantly slowed down (P <0.01), the velocity of skull base artery blood flow was significantly higher than that in control group <0 .05 or P <0 .01). (3) There was a linear positive correlation between plasma NO and microcirculation blood flow velocity in diabetic patients (r = 0.30, P <0.01), and N O was negatively correlated with blood flow velocity in skull base artery (r = -0.0). 75, r = - 0.89, r = - 0.89, P <0 .01). The conclusion shows that N O is in D