%0 Journal Article
%T An experimental study of VEGF induced changes in vasoactivity in pig retinal arterioles and the influence of an anti-VEGF agent
%A Er-Ning Su
%A Stephen J Cringle
%A Ian L McAllister
%A Dao-Yi Yu
%J BMC Ophthalmology
%D 2012
%I BioMed Central
%R 10.1186/1471-2415-12-10
%X An isolated perfused retinal arteriole preparation was used. The outer diameter of retinal vessels was monitored at 2£¿second intervals in response to VEGF and the anti VEGF agent, bevacizumab. The effect of intraluminal delivery of VEGF was determined over a wide concentration range (10-16 to 10-7 M) both with and without pre-contraction with ET-1 (3 x 10-9 M). Bevacizumab (0.35 mg mL-1) was applied extraluminally to determine the influence of bevacizumab on VEGF induced vasoactive changes on ET-1 pre-contracted vessels.In retinal arterioles with normal tone, VEGF induced a concentration dependent contraction at low concentrations, reaching 93.5% at 10-11 M and then contraction was reduced at higher concentrations, recovering to 98.1% at 10-7 M. VEGF produced a potent concentration dependent vasodilatation in arterioles pre-contracted with ET-1. VEGF induced vasodilatation in arterioles pre-contracted with ET-1 was significantly inhibited by bevacizumab.VEGF induced vasoactive changes in pig retinal arterioles are dependent on concentration and vascular tone. Bevacizumab inhibits VEGF-induced vasodilatation in pre-contracted arterioles.Vascular endothelial growth factor (VEGF) is a protein with a high specificity for endothelial cells. In addition to its role in angiogenesis, VEGF also serves multiple important functions including pro-angiogenesis [1], enhancement of vascular permeability [2], changing vascular tone [3-7], and promotion of cell survival [8], division [9], and differentiation [10].Neovascular ocular diseases represent a major cause of vision loss in diseases such as proliferative diabetic retinopathy, age-related macular degeneration, retinopathy of prematurity and retinal vascular occlusions [11]. Elevated VEGF has been found in these diseases [12,13]. VEGF has been considered to be an important pathogenic factor as well as a therapeutic target in ocular neovascularisations and associated changes [14]. Given the introduction of therapeutic intervent
%U http://www.biomedcentral.com/1471-2415/12/10