title: Unique remodeling processes after vascular injury in intracranial arteries: analysis using a novel mouse model.
abstract: The effectiveness of angioplasty and stenting in intracranial atherosclerotic diseases is controversial due to high rates of delayed restenosis and hemorrhage compared with extracranial arteries. However, the mechanisms underlying these differences are still unclear, because their pathophysiology is yet to be examined. To address this issue, we established a novel vascular injury model in the intracranial internal carotid arteries (IICAs) in mice, and analyzed the remodeling process in comparison to that of the femoral arteries (FAs). In IICAs, neointimal hyperplasia was observed from day 14 and grew until day 56. Although smooth muscle cells (SMCs) emerged in the neointima from day 28, SMCs in the injured media were continuously lost with eventual extinction of the media. Re-endothelialization was started from day 7 and completed on day 28. Accumulation of macrophages was continued in the adventitia until day 56. Compared with FAs, the following points are unique in IICAs: (1) delayed continuous formation of neointima; (2) accumulation of macrophages in the media on day 14; (3) continuous loss of SMCs in the media followed by extinction of the media itself; and (4) continuously growing adventitia. These pathophysiologic differences might be associated with unfavorable outcomes in percutaneous transluminal angioplasty and stenting in intracranial arteries.
authors.affiliation: Division of Vascular Medicine and Epigenetics, Department of Child Development, United Graduate School of Child Development, Osaka University Office for University-Industry Collaboration, Osaka, Japan.
authors.forename: Munehisa
authors.initials: M
authors.lastname: Shimamura
authors.forename: Hironori
authors.initials: H
authors.lastname: Nakagami
authors.forename: Masataka
authors.initials: M
authors.lastname: Sata
authors.forename: Minoru
authors.initials: M
authors.lastname: Takaoka
authors.forename: Junya
authors.initials: J
authors.lastname: Azuma
authors.forename: Mariana
authors.initials: M
authors.lastname: Kiomy Osako
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Koriyama
authors.forename: Hitomi
authors.initials: H
authors.lastname: Kurinami
authors.forename: Kouji
authors.initials: K
authors.lastname: Wakayama
authors.forename: Takashi
authors.initials: T
authors.lastname: Miyake
authors.forename: Ryuichi
authors.initials: R
authors.lastname: Morishita
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000494:pharmacology; D002343:Carotid Artery, Internal / Q000473:pathology; D002536:Cerebral Arteries / Q000473:pathology*; D002560:Cerebrovascular Circulation; D002561:Cerebrovascular Disorders / Q000473:pathology*; D016207:Cytokines / Q000134:cerebrospinal fluid; D005263:Femoral Artery / Q000473:pathology; D020287:In Situ Nick-End Labeling; D017078:Laser-Doppler Flowmetry; D008264:Macrophages / Q000473:pathology; D008297:Male; D051379:Mice; D058426:Neointima / Q000473:pathology / Q000517:prevention & control; D020123:Sirolimus / Q000008:administration & dosage / Q000494:pharmacology; D016707:Tissue Fixation
chemical_list: D000900:Anti-Bacterial Agents; D016207:Cytokines; D020123:Sirolimus