Histological changes and ICAM-1 and TMMP-9 expressions in the internal carotid arteries of patients with moyamoya disease / 中华神经医学杂志

ABSTRACT

Objective To observe the histopathological and ultrastructural changes,alterations in the expressions of type Ⅳ collagenases(MMP-2 and MMP-9),the tissue inhibitors(TIMP-1 and TIMP-2)and intercellular adhesion molecule-1(ICAM-1)in the internal carotid arteries(ICAs)of patients with moyamoya disease(MD),and explore the pathogenesis of MD.Methods The bilateral ICAs were obtained during autopsy from two MD patients.HE staining and Weigert staining was used for histological observation,and transmission electron microscopy Was employed to observe the ultrastructure of the ICAS.The expression of ICAM-1 in the ICAs was detected using immunohistochemical staining,and the mRNA expressions of MMLP-2,MMP-9,TMP-1 and TIMP-2 were assayed using in situ hybridization.The ICA specimens from two patients died from non-vascular diseases were used as the control.Restilts HE staining revealed thinning of the ICAs of the MD patients with luminal stenosis,obstruction and calcification.Weigert staining identified fibrous thickening of the intima,thinning and fragmentation of the elastica interna(EI)and elastica externa(EE),degenerafion of the smooth muscle cells in the media,and thinning and local exfoliation of the adventitia.Immunohistochemistry showed ICAM-1 expression in the ICAs of both MD and control patients,but the MD patients exhibited a stronger ICAM-1 positivity in the ICAs localized primarily in the tunica intima.The ICA wall was positive for MMP-9 mRNA expression,which Was especially intense in the elastica intema,as shown by in situ hybfidization.Conslusions The high expression of MMP-9 and ICAM-1,destruction of the elastic layer and adventitia,and collapse of the vascular wall result in luminal stenosis or everi obstruction of the ICAs,which can be associated with the occuITence of MD.