Severity dependent up-regulations of LOX-1 and MCP-1 in early sclerotic changes of common carotid arteries in spontaneously hypertensive rats

• Published in: Neurological research (New York) Vol. 26; no. 7; pp. 767 - 773
• Main Authors: Hamakawa, Y., Omori, N., Ouchida, M., Nagase, M., Sato, K., Nagano, I., Shoji, M., Fujita, T., Abe, K.
• Format: Journal Article
• Language: English
• Published: England Taylor & Francis 01-10-2004; Maney Publishing
• Subjects: Animals; Arteriosclerosis - etiology; Arteriosclerosis - metabolism; ATHEROSCLEROSIS; Biomarkers - metabolism; Body Weight - physiology; Brain - physiology; Carotid Artery, Common - metabolism; Chemokine CCL2 - genetics; Chemokine CCL2 - metabolism; COMMON CAROTID ARTERY; Diet; Hypertension - genetics; Hypertension - pathology; Immunohistochemistry - methods; Lipids - blood; LOX-1; Male; MCP-1; Models, Cardiovascular; Organ Size; Rats; Rats, Inbred SHR; Rats, Inbred WKY; Receptors, LDL - genetics; Receptors, LDL - metabolism; Receptors, Oxidized LDL; Reverse Transcriptase Polymerase Chain Reaction - methods; RNA, Messenger - biosynthesis; Scavenger Receptors, Class E; SHR-SP; Time Factors; Up-Regulation
• ISSN: 0161-6412; 1743-1328
• DOI: 10.1179/016164104225016074

Lectin-like oxidized low-density lipoprotein receptor (LOX-1) and monocyte chemoattractant protein-1 (MCP-1) are molecules involving in the initiation and progression of atherosclerosis. In order to examine a possible difference in LOX-1 and MCP-1 expressions depending on the severity of early stage of atherosclerosis, we investigated atherosclerotic changes by exposure to hypertension and hyperlipidemia in common carotid arteries (CCAs) of stroke-prone spontaneously hypertensive rat (SHR-SP). Three rat model groups such as control [Wistar Kyoto rat (WKY) group], hypertension (SHR-SP group) and hypertension + hyperlipidemia [SHR-SP + high fat and cholesterol (HFC) group] were used. Body weights, brain weights, systolic blood pressures and serum levels of total cholesterol, low-density lipoprotein and triglyceride were measured at 0, 5, 10 and 15 days after appropriate diet. Immunohistochemistry showed that the positive area and the strength of LOX-1 and MCP-1 were larger in the SHR-SP + HFC group than in the SHR-SP group, while no immunoreactivities were found in the WKY group. Conventional RT-PCR and real-time PCR analyses showed that mRNAs of those in the SHR-SP group were higher with greater up-regulation in the SHR-SP + HFC group. LOX-1 and MCP-1 expressions were coordinately up-regulated at mRNA and protein levels in an early stage of sclerosis depending on the severity of atherosclerotic stress. Activations of LOX-1 and MCP-1 are collectively involved in the early stage of atherosclerosis.