Sivitz William I, Wayson Sheila M, Bayless Margaret L, Sinkey Christine A, Haynes William G
Division of Endocrinology and Metabolism, Department of Internal Medicine, Iowa City Veterans Affairs Medical Center and the University of Iowa, Iowa City, IA 52242, USA.
J Diabetes Complications. 2007 May-Jun;21(3):149-57. doi: 10.1016/j.jdiacomp.2005.12.003.
Arterial dysfunction occurs in obesity and diabetes. However, there is uncertainty about the relative contribution of endothelial dysfunction, smooth muscle dysfunction, or adrenergic hyperresponsiveness.
We examined forearm resistance vessel responses to intra-arterial vasoactive agents in matched subjects on no antihyperglycemic medications classified as (1) Type 2 diabetes, (2) impaired fasting glucose (IFG), (3) obese, and (4) nonobese. Responses to both acetylcholine and nitroprusside were impaired in obese, IFG, and diabetic subjects compared to nonobese. However, diabetic and IFG subjects had no further impairment than normoglycemic obese subjects. Gender-specific data revealed that obese, IFG, and diabetic males compared to nonobese males demonstrated impaired responses to nitroprusside. However, among females, obese, IFG, and diabetic subjects demonstrated impaired acetylcholine-mediated responses. Multivariate analyses revealed that gender and adiposity, but not glycemia, were strongly related to acetylcholine and nitroprusside responses. Vasoconstriction to norepinephrine was greater in subjects with diabetes and IFG compared to nondiabetic obese controls.
Microvascular vasodilator function is impaired in obesity, with little further impairment in IFG and Type 2 diabetes. Females appear more sensitive to the deleterious effect of obesity on endothelium-mediated resistance vessel function, and males to smooth muscle-mediated function. There is a specific increase in adrenergic vasoconstrictor responses in IFG and Type 2 diabetes independent of obesity.
肥胖和糖尿病患者会出现动脉功能障碍。然而，关于内皮功能障碍、平滑肌功能障碍或肾上腺素能反应过度的相对作用尚不确定。
我们在未服用抗高血糖药物的匹配受试者中，检测了前臂阻力血管对动脉内血管活性药物的反应，这些受试者分为四类：（1）2型糖尿病患者；（2）空腹血糖受损（IFG）者；（3）肥胖者；（4）非肥胖者。与非肥胖者相比，肥胖者、IFG患者和糖尿病患者对乙酰胆碱和硝普钠的反应均受损。然而，糖尿病患者和IFG患者的受损程度并不比血糖正常的肥胖者更严重。按性别分类的数据显示，与非肥胖男性相比，肥胖男性、IFG男性和糖尿病男性对硝普钠的反应受损。然而，在女性中，肥胖者、IFG患者和糖尿病患者对乙酰胆碱介导的反应受损。多变量分析显示，性别和肥胖程度而非血糖水平与乙酰胆碱和硝普钠的反应密切相关。与非糖尿病肥胖对照组相比，糖尿病患者和IFG患者对去甲肾上腺素的血管收缩反应更强。
肥胖患者的微血管舒张功能受损，IFG患者和2型糖尿病患者的受损程度进一步加重。女性似乎对肥胖对内皮介导的阻力血管功能的有害影响更为敏感，而男性则对平滑肌介导的功能更为敏感。IFG患者和2型糖尿病患者的肾上腺素能血管收缩反应有特定增加，且与肥胖无关。
