[Pathophysiological roles of matrix metalloproteinases and nitric oxide synthase in cerebral aneurysm]

To explore the expressions of matrix metalloproteinases-2 (MMP-2), matrix metalloproteinases-9 (MMP-9) and inducible nitric oxide synthase (iNOS) in cerebral aneurysms, compare them with normal brain vessels tissue so as to gain a better understanding of the pathogenesis of cerebral aneurysms.

Twelve samples of cerebral aneurysms were obtained during operations and 10 cortical arteries as controls during surgery for temporal lobe epilepsy from 2009 to 2012 at Inner Mongolia People's Hospital and Beijing Tiantan Hospital. The activities of MMP-2, MMP-9 and iNOS in specimens were detected with spectrophotometry and substrate gel zymography.

The MMP-2 and MMP-9 levels in cerebral aneurysm group were (199 598 ± 125 288) gray scale area × mg⁻¹ × L⁻¹ and (719 253 ± 376 519) gray scale area × mg⁻¹ × L⁻¹. Both in cerebral aneurysm group were significantly higher than that in control group (P < 0.05) . The TNOS and iNOS levels in cerebral aneurysm group were (23.6 ± 6.6) and (11.4 ± 2.6) U/mgprot. The difference of TNOS level was not significant between aneurysm and control groups (P > 0.05) while the levels of iNOS and iNOS/TNOS in cerebral aneurysm group were significantly higher than that in control group (P < 0.05).

MMP-2, MMP-9 and iNOS are closely correlated with cerebral aneurysm.