Eutrophic structural remodeling of hypertensive and type 1 diabetic mouse mesenteric resistance artery

Hypertension and type 1 diabetes are associated with vasculopathy. We determined the nature of resistance artery structural remodeling in association with increased collagen type 1 content and stiffness. Methods and Results: C57/bl6 mice were perfused with hypertensive dose of angiotensin II (AII, 200 ng/kg/day) or injected with one single dose of STZ (150 mg/kg/) for 3 days and 4 weeks. Blood pressure was high in mice infused with AII for 4 weeks compared to sham. Blood glucose was significantly increased 2 days after STZ injection. Freshly isolated MRA were mounted in arteriograph and submitted to pressure changes. After 3 days of hypertension or type 1 diabetes, data indicated an increase of wall thickness in combination with small diameter, lumen:diameter ratio (0.15±0.01, 0.2±0.013 vs. 0.11±0.02% at 75 mmHg, STZ, AII vs. sham respectively), remodeling index (13±1.2% at 75 mmHg) and stiffness indicating a structural remodeling initiation of resistance arteries. After 4 weeks of hypertension or type 1 diabetes, lumen:diameter ratio (0.3±0.02% at 75 mmHg), remodeling index (38% at 75 mmHg) and stiffness of MRA were enhanced compared to 3 days treatment. After 4 weeks, collagen type 1 content was significantly higher in MRA from hypertensive and type 1 diabetic compared to sham mice. Conclusion: This study indicated the initiation and the establishment of a similar eutrophic structural remodeling of hypertensive or type 1 diabetic mouse MRA. The structural remodeling was associated with increased collagen type 1 content and stiffness.