RESUMO
<p><b>OBJECTIVE</b>To investigate the effects of saturated hydrogen saline on the prevention of abdominal aortic aneurysm (AAA) induced by calcium chloride in a rat model.</p><p><b>METHODS</b>In healthy male Sprague-Dawley rats, AAA was induced by infiltration of abdominal arota with 0.5 mol/L calcium chloride. Saturated hydrogen saline (5 ml·kg(-1)·d(-1)) or saline was administred intraperitoneally once daily. Twenty-eight days later, the diameter of the aorta was measured, and the aortic tissue was exercised for histological examination. Pro-inflammatory cytokines (tumor necrosis factor α (TNF-α), IL-1β) in AAA tissue were detected with ELISA. The protein expression and mRNA expression of matrix metalloproteinase 2 (MMP-2) and MMP-9 in AAA tissue were observed by immunohistochemistry staining and real-time PCR.</p><p><b>RESULT</b>The aorta diameter of the experiment group and control group were (2.2 ± 0.3) mm and (3.4 ± 0.5) mm, the tissue IL-1β levels were (81 ± 29) ng/L and (165 ± 51) ng/L, the tissue TNF-α levels were (109 ± 46) ng/L and (360 ± 51) ng/L, the relative mRNA expressions were 2.4 ± 1.0 and 11.8 ± 2.9, the relative mRNA expressions were 2.9 ± 0.6 and 6.7 ± 1.0 (t = 4.055 to 10.406, P < 0.05). Compared with the control group, the infiltration of inflammation, the injury of elastic fibers in the vessel wall, and the positive expression of MMP-2 and 9 protein of the experiment group were all reduced.</p><p><b>CONCLUSIONS</b>Saturated hydrogen saline prevents the degradation of elastin in vessel wall and ameliorates the formation and development of AAA, which may be associated with its anti-inflammatory effects, thereby reduces the MMP-2 and 9 mRNA and protein expression.</p>