Manganese porphyrin reduces retinal injury induced by ocular hypertension in rats.

Published

Journal Article

This study aimed to clarify the possible therapeutic benefit of preferential nitric oxide synthase (NOS) inhibition and catalytic antioxidant Mn (III) meso-tetrakis (N-n-hexylpyridinium-2-yl) porphyrin (MnTnHex-2-PyP(5+)) treatment in a rat model of elevated intraocular pressure (EIOP). Rats were randomly divided into different experimental groups which received either intraperitoneal MnTnHex-2-PyP(5+) (0.1 mg/kg/day), intragastric NOS inhibitor (S-methylthiourea: SMT; 5 mg/kg/day) or both agents for a period of 6 weeks. Ocular hypertension was induced by unilaterally cauterizing three episcleral vessels and the unoperated eye served as control. Neuroprotective effects of given treatments were determined via electrophysiological measurements of visual evoked potentials (VEP) while retina and vitreous levels of MnTnHex-2-PyP(5+) were measured via LC-MS/MS. Latencies of all VEP components (P(1), N(1), P(2), N(2), P(3)) were significantly prolonged (p < 0.05) in EIOP and returned to control levels following all three treatment protocols. Ocular hypertension significantly increased retinal protein nitration (p < 0.001) which returned to baseline levels in all treated groups. NOS-2 expression and nitrate/nitrite levels were significantly greater in non-treated rats with EIOP. Retinal TUNEL staining showed apoptosis in all ocular hypertensive rats. The presented data confirm the role of oxidative injury in EIOP and highlight the protective effect of MnTnHex-2-PyP(5+) treatment and NOS inhibition in ocular hypertension.

Full Text

Duke Authors

Cited Authors

  • Dogan, S; Unal, M; Ozturk, N; Yargicoglu, P; Cort, A; Spasojevic, I; Batinic-Haberle, I; Aslan, M

Published Date

  • October 2011

Published In

Volume / Issue

  • 93 / 4

Start / End Page

  • 387 - 396

PubMed ID

  • 21669199

Pubmed Central ID

  • 21669199

Electronic International Standard Serial Number (EISSN)

  • 1096-0007

International Standard Serial Number (ISSN)

  • 0014-4835

Digital Object Identifier (DOI)

  • 10.1016/j.exer.2011.05.008

Language

  • eng