The aim of this study was to evaluate resistance arteries from diabetic patients with controlled hypertension. Nine normotensive (44±3 years, 3 male),
11 untreated hypertensive (51±2 years, 9 male) and 15 hypertensive subjects with type 2 diabetes mellitus under antihypertensive treatment (58±2 years,
11 male) were studied. Resistance arteries were dissected from gluteal subcutaneous tissue and assessed on a pressurized myograph. 73% of the diabetic patients were treated with an ACE inhibitor. Systolic blood pressure was 143±2.6 vs. 139±2.8 mmHg in hypertensive diabetic individuals vs. non diabetic hypertensive subjects, and 112±4.3 mmHg in normotensive subjects, whereas diastolic blood pressure was well controlled in diabetic patients (84±2.1 mmHg), and lower compared to untreated hypertensive patients (92±1.6 mmHg, p<0.05), although higher than in normotensive controls (75±2.4 mmHg, p=0.014). Thus pulse pressure was significantly higher in the diabetic patients compared to the other groups (p<0.05). Diabetes was controlled mainly with oral hypoglycemic agents with HbA1c= 7.1±1.1%. In resistance arteries, the media to lumen ratio was significantly increased in hypertensive patients (8.4±0.5%) compared to controls (5.9±0.3%, p<0.05) and was higher in diabetic patients (9.4±0.7%, p<0.01 vs control). Cross sectional area of the media was significantly higher in diabetic and hypertensive patients compared to controls (p<0.01), indicating hypertrophic remodeling. Acetylcholine-induced relaxation was impaired in vessels from hypertensive patients (p<0.05), with vessels from diabetic patients showing the same trend, whereas endothelium-independent vasorelaxation was similar in all groups. Vascular remodeling of resistance arteries appears to be more severe in diabetic patients with well-controlled hypertension than in non diabetic hypertensive individuals, and could be more resistant to correction by antihypertensive treatment.

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