Critical Role of Monocyte Chemoattractant Protein-1 Receptor CCR2 on Monocytes in Hypertension-Induced Vascular Inflammation and Remodeling

• Published in: Circulation research 2004-05, Vol.94 (9), p.1203-1210
• Main Authors: Ishibashi, Minako, Hiasa, Ken-ichi, Zhao, Qingwei, Inoue, Shujiro, Ohtani, Kisho, Kitamoto, Shiro, Tsuchihashi, Miyuki, Sugaya, Takeshi, Charo, Israel F, Kura, Shinobu, Tsuzuki, Teruhisa, Ishibashi, Tatsuro, Takeshita, Akira, Egashira, Kensuke
• Format: Article
• Language: English
• Subjects: Angiotensin II - toxicity; Angiotensin II Type 1 Receptor Blockers; Animals; Aorta - drug effects; Aorta - metabolism; Biological and medical sciences; Bone Marrow Transplantation; Chemokine CCL2 - biosynthesis; Chemokine CCL2 - genetics; Chemotaxis, Leukocyte - physiology; Enzyme Inhibitors - pharmacology; Fundamental and applied biological sciences. Psychology; Humans; Hypertension - chemically induced; Hypertension - metabolism; Hypertrophy, Left Ventricular - etiology; Hypertrophy, Left Ventricular - metabolism; Imidazoles - pharmacology; Inflammation - metabolism; Infusion Pumps, Implantable; Male; Mice; Mice, Inbred C57BL; Monocytes - drug effects; Monocytes - physiology; NG-Nitroarginine Methyl Ester - pharmacology; Nitric Oxide Synthase - antagonists & inhibitors; Nitric Oxide Synthase Type II; Nitric Oxide Synthase Type III; Olmesartan Medoxomil; Pilot Projects; Radiation Chimera; Rats; Rats, Inbred SHR; Rats, Inbred WKY; Receptor, Angiotensin, Type 1 - deficiency; Receptor, Angiotensin, Type 1 - genetics; Receptors, CCR2; Receptors, Chemokine - deficiency; Receptors, Chemokine - genetics; Receptors, Chemokine - physiology; Recombinant Fusion Proteins - physiology; Superoxide Dismutase - genetics; Tetrazoles - pharmacology; Up-Regulation - drug effects; Vertebrates: cardiovascular system
• ISSN: 0009-7330; 1524-4571
• DOI: 10.1161/01.RES.0000126924.23467.A3

Activated monocytes are present in the arterial walls of hypertensive patients and animals. Monocyte chemoattractant protein-1 (MCP-1), which controls monocyte function through its receptor (CCR2), is implicated in hypertensive inflammatory changes in the arterial wall. The role of CCR2 expression on monocytes in hypertension-induced vascular remodeling, however, has not been addressed. We hypothesized that CCR2 on monocytes is critical in hypertension-induced vascular inflammation and remodeling. Hypertension was induced by infusion of angiotensin II (Ang II) into wild-type mice, CCR2-deficient (CCR2) mice, and bone marrow-transferred mice with a leukocyte-selective CCR2 deficiency (BMT-CCR2). In wild-type mice, Ang II increased CCR2 intensity in circulating monocytes, which was prevented by an Ang II type-1 (AT1) receptor blocker or blunted in AT1 receptor–deficient mice. Enhanced CCR2 intensity on monocytes was observed in hypertensive patients and rats, and was reduced by treatment with the Ang II receptor blocker, supporting the clinical relevance of the observation in mice. In CCR2 and BMT-CCR2 mice, Ang II–induced vascular inflammation and vascular remodeling (aortic wall thickening and fibrosis) were blunted as compared with control mice. In contrast, Ang II–induced left ventricular hypertrophy developed in CCR2 and BMT-CCR2 mice. The present study suggests that CCR2 expression in monocytes has a critical role in vascular inflammation and remodeling in Ang II–induced hypertension, and possibly in other forms of hypertension.