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OBJECTIVES: To determine whether β-adrenergic blockade inhibits choroidal neovascularization (CNV) in a mouse model of laser-induced CNV and to investigate the mechanism by which β-adrenoreceptor antagonism blunts CNV. DESIGN: Mice were subjected to laser burns, inducing CNV, and were treated with daily intraperitoneal injections of propranolol hydrochloride. Neovascularization was measured on choroidal-scleral flat mounts using intercellular adhesion molecule 2 immunofluorescence staining. The effect of β-adrenoreceptor signaling on expression of vascular endothelial growth factor (VEGF) was investigated using primary mouse choroidal endothelial cells (ChECs) and retinal pigment epithelial (RPE) cells. These cells were incubated with β-adrenoreceptor agonists and/or antagonists and assayed for Vegf messenger RNA and protein levels. SETTING: University of Wisconsin School of Medicine and Public Health. PARTICIPANTS: Wild-type 6-week-old female C57BL/6j mice. MAIN OUTCOME MEASURES: Inhibition of CNV after propranolol treatment and Vegf messenger RNA and protein expression after treatment with β-adrenoreceptor agonists and antagonists. RESULTS: Propranolol-treated mice demonstrated a 50% reduction in laser-induced CNV. Treatment with norepinephrine bitartrate stimulated Vegf messenger RNA expression and protein secretion in ChECs and RPE cells. This effect was blocked by β2-adrenoreceptor antagonism and mimicked by β2-adrenoreceptor agonists. CONCLUSIONS: Attenuation of CNV is achieved by β-adrenergic blockade. The β2-adrenoreceptors regulate VEGF expression in ChECs and RPE cells. CLINICAL RELEVANCE: Antagonists of β-adrenoreceptors are safe and well tolerated in patients with glaucoma and cardiovascular disease. Thus, blockade of β-adrenoreceptors may provide a new avenue to inhibit VEGF expression in CNV.
Departments of Ophthalmology and Visual Science, University of Wisconsin School of Medicine and Public Health, Madison, WI 53792, USA.
Full article11.3.4 Betablocker (Part of: 11 Medical treatment > 11.3 Adrenergic drugs)
5.1 Rodent (Part of: 5 Experimental glaucoma; animal models)
11.14 Investigational drugs; pharmacological experiments (Part of: 11 Medical treatment)