Increased Vascular Cell Adhesion Molecule–1 Was Associated with Impaired Endothelium–Dependent Relaxation of Cerebral and Carotid Arteries in Simulated Microgravity Rats

抄録

The aim of the present study was to investigate whether expression of vascular cell adhesion molecule–1 (VCAM-1) was upregulated in 3-week simulated microgravity rat cerebral and carotid arteries and whether impaired endothelium–dependent relaxation was concomitant with VCAM-1 expression. Male Sprague-Dawley rats were randomly divided into control (CON) and hindlimb unweighting (HU) groups. After 3 weeks, expression of VCAM-1 protein and vasodilatation of basilar artery and common carotid artery were determined. Immunohistochemical results revealed positive staining of VCAM-1 on endothelial cells in basilar artery and common carotid artery from HU compared with CON rats. Western blot analysis confirmed upregulated expression of VCAM-1 protein in these arteries from HU rats. Acetylcholine induced concentration-dependent vasodilatation in all artery rings, but with significantly smaller amplitude in basilar artery (P < 0.01) and common carotid artery (P < 0.05) from HU than those from CON rats. The data suggested that expression of VCAM-1 protein was upregulated in cerebral and common carotid arteries of simulated microgravity rats and the upregulation of VCAM-1 may contribute to impaired endothelium–dependent relaxation in simulated microgravity rat vasculature.