Vasodilatory effects of antivascular endothelium growth factor (VEGF) antibody, corticosteroid, and nitric oxide on the posterior ciliary arteries
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The purpose of this study was to determine whether an antivascular endothelium growth factor (VEGF) antibody, a corticosteroid, and sodium nitroprusside (SNP) [a nitric oxide (NO) donor] are possible treatment agents for nonarteritic ischemic optic neuropathy (NAION) by clarifying their effects on high-K (potassium) solution-induced contraction in isolated rabbit and human posterior ciliary arteries (PCA).
Vascular ring segments were cut from the distal section of the PCA and mounted in a double-myograph system. After obtaining the maximal contraction following the administration of high-K solution, bevacizumab as an anti-VEGF antibody, methylprednisolone as a corticosteroid, and SNP were administered separately. When a vasodilatory effect was observed, carboxy-PTIO (a NO scavenger) or l-NAME (a NO synthase inhibitor) was administered.
Bevacizumab did not relax either the rabbit or the human PCA, whereas methylprednisolone relaxed both. Neither carboxy-PTIO nor l-NAME inhibited methylprednisolone-induced relaxation. SNP relaxed the rabbit PCA. Carboxy-PTIO inhibited SNP-induced relaxation, but l-NAME did not. In the human PCA, the vasodilatory effect of SNP was present, but weaker than in the rabbit PCA.
A corticosteroid has NO-independent vasodilatory effects. Exogenous NO has a weak dilating effect in the human PCA. Therefore, corticosteroid could be effective for the treatment of NAION.
KeywordsAnti-VEGF antibody Corticosteroid Nitric oxide Posterior ciliary artery Vasodilatory effect
- 1.Arnold AC. Ischemic optic neuropathy. In: Miller NR, Newman NJ, editors. Walsh & Hoyt’s clinical neuro-ophthalmology. 6th ed. Philadelphia: Lippincott Williams & Wilkins; 2005. p. 349–84.Google Scholar
- 15.Chuman H, Maekubo T, Oosako T, Kodama Y, Ishiai M, Nao-I N. Confirmation of rodent model of non-arteritic ischemic optic neuropathy and its electrophysiological evaluation. Jpn J Ophthalmol. 2012 [Epub ahead of print].Google Scholar
- 17.Hsueh WA, Quinones MJ, Creager MA. Endothelium in insulin resistance and diabetes. Diabetes Rev. 1997;5:343–52.Google Scholar