TY - JOUR
T1 - Mecamylamine suppresses basal and nicotine- stimulated choroidal neovascularization
AU - Kiuchi, Katsuji
AU - Matsuoka, Masato
AU - Wu, Jenny C.
AU - Silva, Raquel Lima E.
AU - Kengatharan, Muralitharan
AU - Verghese, Mary
AU - Ueno, Shinji
AU - Yokoi, Katsutoshi
AU - Khu, Naw Htee
AU - Cooke, John P.
AU - Campochiaro, Peter A.
N1 - Copyright:
Copyright 2012 Elsevier B.V., All rights reserved.
PY - 2008/4
Y1 - 2008/4
N2 - Purpose. Nicotinic acetylcholine receptors (nAChR) are best known for their role in neurotransmission, but they have recently been demonstrated on vascular endothelial cells. Ace- tylcholine is their endogenous ligand, but they are also stimulated by nicotine. By stimulating nAChR, nicotine promotes tumor angiogenesis as well as atherosclerotic plaque neovas- cularization. In this study, the authors investigated the role of nAChR in the pathogenesis of choroidal neovascularization (CNV). methods. The effect of the nonselective nAChR antagonist mecamylamine was tested on human retinal and choroidal endothelial cells in vitro and in a murine model of CNV. Results. Several nAChR isoforms were identified in retinal and choroidal microvascular endothelial cells, and the ability of these cells to form tubules when grown in growth factor- reduced basement membrane matrix and supplemented with VEGF was suppressed by the nAChR antagonist mecamylamine. Supplementation of the drinking water of mice with nicotine increased the size of CNV lesions at Bruch membrane rupture sites, an effect that was blocked by subcutaneous administration of mecamylamine (50 mg/ kg/d) by an osmotic pump. In the absence of nicotine, CNV formation was suppressed by the infusion of 50 mg/kg/d mecamylamine or by topical application 0.1 or 1% mecamylamine to the cornea. Conclusions. These data suggest that endogenous activation of nAChR promotes CNV and that activation of nAChR by nicotine may contribute to the increased incidence of CNV seen in smokers with age-related moacular degeneration (AMD). Topically admainistered mecamylamaine could provide an appealing new treatment approach for CNV.
AB - Purpose. Nicotinic acetylcholine receptors (nAChR) are best known for their role in neurotransmission, but they have recently been demonstrated on vascular endothelial cells. Ace- tylcholine is their endogenous ligand, but they are also stimulated by nicotine. By stimulating nAChR, nicotine promotes tumor angiogenesis as well as atherosclerotic plaque neovas- cularization. In this study, the authors investigated the role of nAChR in the pathogenesis of choroidal neovascularization (CNV). methods. The effect of the nonselective nAChR antagonist mecamylamine was tested on human retinal and choroidal endothelial cells in vitro and in a murine model of CNV. Results. Several nAChR isoforms were identified in retinal and choroidal microvascular endothelial cells, and the ability of these cells to form tubules when grown in growth factor- reduced basement membrane matrix and supplemented with VEGF was suppressed by the nAChR antagonist mecamylamine. Supplementation of the drinking water of mice with nicotine increased the size of CNV lesions at Bruch membrane rupture sites, an effect that was blocked by subcutaneous administration of mecamylamine (50 mg/ kg/d) by an osmotic pump. In the absence of nicotine, CNV formation was suppressed by the infusion of 50 mg/kg/d mecamylamine or by topical application 0.1 or 1% mecamylamine to the cornea. Conclusions. These data suggest that endogenous activation of nAChR promotes CNV and that activation of nAChR by nicotine may contribute to the increased incidence of CNV seen in smokers with age-related moacular degeneration (AMD). Topically admainistered mecamylamaine could provide an appealing new treatment approach for CNV.
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U2 - 10.1167/iovs.07-0089
DO - 10.1167/iovs.07-0089
M3 - Article
C2 - 18385094
AN - SCOPUS:45549103174
SN - 0146-0404
VL - 49
SP - 1705
EP - 1711
JO - Investigative Ophthalmology and Visual Science
JF - Investigative Ophthalmology and Visual Science
IS - 4
ER -