Bacterial Lipopolysaccharide Induces Early Preconditioning and Postconditioning in the Rat Retina

FRANCO PJ; FERNANDEZ, DIEGO; ROSENSTEIN R.E

Fort Lauderdale, USA

Congreso; The Association for Research in Vision and Ophthalmology; 2009

The Association for Research in Vision and Ophthalmology

Invest Ophthalmol Vis Sci 2009;50: E-Abstract 377.© 2009 ARVO 377—A61 Bacterial Lipopolysaccharide Induces Early Preconditioning and Postconditioning in the Rat RetinaP. J. Franco, D. C. Fernandez and R. E. Rosenstein Department of Human Biochemestry, School of Medicine, University of Buenos Aires, Argentina Commercial Relationships: P.J. Franco, None; D.C. Fernandez, None; R.E. Rosenstein, None. Support: BID 1728 PICT 25364 Abstract Purpose:In a previous report, we showed that intravitreal injections of bacterial lipopolysaccharide (LPS), 24 h before ischemia induce late ischemic preconditioning. The aim of this study was to investigate whether LPS triggers early preconditioning and postconditioning in the rat retina. Methods:Rats were intravitreously injected with 3 µg LPS in one eye and vehicle in the contralateral eye, 30 or 60 min before, or 15 or 60 min after retinal ischemia induced by increasing intraocular pressure to 120 mmHg for 40 min. Subsequently, 7 or 14 days after ischemia, rats were subjected to electroretinography and histological analysis by light microscopy of retinal sections. Results:Ischemia for 40 min and reperfusion for 7 or 14 days induced a significant decrease in scotopic ERG a- and b-wave amplitude. The ischemia-induced decrease in both a- and b-wave amplitude was significantly lower in eyes injected with 3 µg LPS 60 min (but not 30 min) before and 15 and 60 min after ischemia. Moreover, histological examination revealed that ischemia-associated structural damage and loss of cells in the outer and inner nuclear layers were largely prevented by LPS injected 60 min (but not 30 min) before or 15 and 60 min after ischemia. Conclusions:For the first time, these results indicate that LPS triggered early preconditioning and postconditioning in the rat retina, providing a significant functional and histological protection against ischemia/reperfusion damage. Keywords: retina • ischemia • neuroprotection © 2009, The Association for Research in Vision and Ophthalmology, Inc., all rights reserved. Permission to republish any abstract or part of an abstract in any form must be obtained in writing from the ARVO Office prior to publication.