The effects of iodoacetic acid on the mouse retina

• Published in: Graefe's archive for clinical and experimental ophthalmology 2015-01, Vol.253 (1), p.25-35
• Main Authors: Rösch, Sarah, Johnen, Sandra, Mazinani, Babac, Müller, Frank, Pfarrer, Christiane, Walter, Peter
• Format: Article
• Language: English
• Subjects: Animals; Cataract - chemically induced; Cataract - pathology; Electroretinography - drug effects; Enzyme Inhibitors - toxicity; Female; Injections, Intravenous; Intravitreal Injections; Iodoacetic Acid - toxicity; Medicine; Medicine & Public Health; Mice; Mice, Inbred C57BL; Ophthalmology; Retina - drug effects; Retina - metabolism; Retinal Degeneration - chemically induced; Retinal Degeneration - pathology; Retinal Disorders; Tomography, Optical Coherence
• ISSN: 0721-832X; 1435-702X
• DOI: 10.1007/s00417-014-2652-0

Background To characterize the effects of intravitreal injections of iodoacetic acid (IAA) in comparison to its systemic application as a measure to induce unilateral photoreceptor degeneration. Methods Seven-week-old C57BL/6 J mice received either intravitreal injections of IAA or systemic treatment (intraperitoneal vs intravenous) and were observed in the following 5 weeks using ERG, OCT, and histology. Results Systemic treatment with IAA induced high toxic effects and a high mortality in contrast to the intravitreal injection. Intraperitoneal application had no effect on the retina. Intravenous application of 2 × 30 mg/kg BW IAA (time between injections 3.5 h) resulted in an extinction of the ERG and a thinning of the retina, in particular of the outer nuclear layer (ONL) indicating photoreceptor degeneration. Animals receiving intravitreal injections developed cataracts already at low concentrations (up to 100 % at 0.25 mg/kg BW). Higher intravitreal IAA doses led to extinguished ERGs. In histology, a thinning of the entire retina was observed that was most prominent in the inner part of the retina. Conclusions In contrast to intraperitoneal administration, intravenous application of IAA led to a selective photoreceptor degeneration. After intravitreal injection, dense cataracts were already observed at concentrations lower than those needed to induce changes in the ERG. ERG results must be interpreted carefully. A thinning of all retinal layers rather than a specific outer retinal degeneration was observed upon intravitreal injection. IAA is not a useful model to induce outer retinal degeneration in mice.