John S. Penn, Ph.D.

Professor

john.s.penn@vanderbilt.edu

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Faculty Appointments
Associate Dean for Faculty Affairs Professor of Ophthalmology and Visual Sciences Phyllis G. and William B. Snyder, MD Endowed Chair in Ophthalmology and Visual SciencesProfessor of Cell and Developmental BiologyProfessor of Medical Education and Administration
Education
Ph.D., Biology, Florida State University, Tallahassee, FloridaM.S., Biology, University of West Florida, Pensacola, FloridaB.A., Biology, University of the South, Sewanee, Tennessee
Office Address
2115 21st Ave. S., 8009 MCE
Vanderbilt Eye Institute
Nashville, TN 37232-8808
Research Description
Penn's long-standing interest is in the molecular basis of retinal vascular disease. The over-reaching goal of his research is to characterize the processes involved in retinal vascular inflammation and angiogenesis, and to begin to develop preventive strategies based on understanding gained from in vitro and in vivo studies. The Penn lab has the capability to isolate and culture a variety of primary cells from retinal tissue of several species, including retinal vascular endothelial cells, choroidal endothelial cells, retinal Müller glia, retinal pericytes and retinal pigment epithelial cells – all of which are involved in vascular diseases of the retina. In addition, the lab uses a battery of in vivo models of vascular diseases of the eye including rodent models of retinopathy of prematurity, neovascular age-related degeneration and diabetic retinopathy. Using these in vitro and in vivo tools, Penn's research program focuses on pro-inflammatory and pro-angiogenic molecular signaling in the retina with an emphasis on drug target identification, and development of novel targeted therapies and mechanisms of drug delivery to the eye.

Penn has been continuously funded by the National Eye Institute of NIH for 30 years. He is currently the President of the International Society for Eye Research.
Research Keywords
Angiogenesis, vasculogenesis, retinopathy, vascular inflammation, VEGF, inflammatory cytokines, vascular biology, molecular biology, cell biology, retinopathy of prematurity, macular degeneration, diabetic retinopathy
Clinical Research Keywords
ocular angiogenesis, retinopathy of prematurity, diabetic retinopathy, neovascular macular degeneration
Publications
Suarez S, McCollum GW, Jayagopal A, Penn JS. High Glucose-induced Retinal Pericyte Apoptosis Depends on Association of GAPDH and Siah1. J. Biol. Chem [print-electronic]. 2015 Nov 11/20/2015; 290(47): 28311-20. PMID: 26438826, PMCID: PMC4653686, PII: M115.682385, DOI: 10.1074/jbc.M115.682385, ISSN: 1083-351X.

Savage SR, McCollum GW, Yang R, Penn JS. RNA-seq identifies a role for the PPARß/d inverse agonist GSK0660 in the regulation of TNFa-induced cytokine signaling in retinal endothelial cells. Mol. Vis. 2015; 21: 568-76. PMID: 26015769, PMCID: PMC4443583, ISSN: 1090-0535.

Savage SR, Bretz CA, Penn JS. RNA-Seq reveals a role for NFAT-signaling in human retinal microvascular endothelial cells treated with TNFa. PLoS ONE. 2015; 10(1): e0116941. PMID: 25617622, PMCID: PMC4305319, PII: PONE-D-14-43273, DOI: 10.1371/journal.pone.0116941, ISSN: 1932-6203.

Bretz CA, Savage SR, Capozzi ME, Suarez S, Penn JS. NFAT isoforms play distinct roles in TNFa-induced retinal leukostasis. Sci Rep. 2015; 5: 14963. PMID: 26527057, PMCID: PMC4630625, PII: srep14963, DOI: 10.1038/srep14963, ISSN: 2045-2322.

Suarez S, McCollum GW, Bretz CA, Yang R, Capozzi ME, Penn JS. Modulation of VEGF-induced retinal vascular permeability by peroxisome proliferator-activated receptor-ß/d. Invest. Ophthalmol. Vis. Sci. 2014 Dec; 55(12): 8232-40. PMID: 25406289, PMCID: PMC4271638, PII: iovs.14-14217, DOI: 10.1167/iovs.14-14217, ISSN: 1552-5783.

Barnett JM, Suarez S, McCollum GW, Penn JS. Endoglin promotes angiogenesis in cell- and animal-based models of retinal neovascularization. Invest. Ophthalmol. Vis. Sci. 2014 Oct; 55(10): 6490-8. PMID: 25159209, PMCID: PMC4197712, PII: iovs.14-14945, DOI: 10.1167/iovs.14-14945, ISSN: 1552-5783.

Capozzi ME, McCollum GW, Penn JS. The role of cytochrome P450 epoxygenases in retinal angiogenesis. Invest. Ophthalmol. Vis. Sci. 2014 Jul; 55(7): 4253-60. PMID: 24917142, PMCID: PMC4098062, PII: iovs.14-14216, DOI: 10.1167/iovs.14-14216, ISSN: 1552-5783.

Madamanchi A, Capozzi M, Geng L, Li Z, Friedman RD, Dickeson SK, Penn JS, Zutter MM. Mitigation of oxygen-induced retinopathy in a2ß1 integrin-deficient mice. Invest. Ophthalmol. Vis. Sci. 2014 Jul; 55(7): 4338-47. PMID: 24917135, PMCID: PMC4102391, PII: iovs.14-14061, DOI: 10.1167/iovs.14-14061, ISSN: 1552-5783.

Watkins WM, McCollum GW, Savage SR, Capozzi ME, Penn JS, Morrison DG. Hypoxia-induced expression of VEGF splice variants and protein in four retinal cell types. Exp. Eye Res [print-electronic]. 2013 Nov; 116: 240-6. PMID: 24076411, PMCID: PMC4256053, PII: S0014-4835(13)00280-7, DOI: 10.1016/j.exer.2013.09.014, ISSN: 1096-0007.

Bretz CA, Savage S, Capozzi M, Penn JS. The role of the NFAT signaling pathway in retinal neovascularization. Invest. Ophthalmol. Vis. Sci. 2013 Oct; 54(10): 7020-7. PMID: 24052639, PMCID: PMC3809948, PII: iovs.13-12183, DOI: 10.1167/iovs.13-12183, ISSN: 1552-5783.

Capozzi ME, McCollum GW, Savage SR, Penn JS. Peroxisome proliferator-activated receptor-ß/d regulates angiogenic cell behaviors and oxygen-induced retinopathy. Invest. Ophthalmol. Vis. Sci. 2013 Jun; 54(6): 4197-207. PMID: 23716627, PMCID: PMC3687964, PII: iovs.13-11608, DOI: 10.1167/iovs.13-11608, ISSN: 1552-5783.

Capozzi ME, Gordon AY, Penn JS, Jayagopal A. Molecular imaging of retinal disease. J Ocul Pharmacol Ther [print-electronic]. 2013 Mar; 29(2): 275-86. PMID: 23421501, PMCID: PMC3601716, DOI: 10.1089/jop.2012.0279, ISSN: 1557-7732.

Barnett JM, Penn JS, Jayagopal A. Imaging of endothelial progenitor cell subpopulations in angiogenesis using quantum dot nanocrystals. Methods Mol. Biol. 2013; 1026: 45-56. PMID: 23749568, DOI: 10.1007/978-1-62703-468-5_4, ISSN: 1940-6029.

Rezaei KA, Toma HS, Cai J, Penn JS, Sternberg P, Kim SJ. Reduced choroidal neovascular membrane formation in cyclooxygenase-2 null mice. Invest. Ophthalmol. Vis. Sci [electronic-print]. 2011 Feb; 52(2): 701-7. PMID: 20881304, PMCID: PMC3053102, PII: iovs.10-6319, DOI: 10.1167/iovs.10-6319, ISSN: 1552-5783.

Toma HS, Barnett JM, Penn JS, Kim SJ. Improved assessment of laser-induced choroidal neovascularization. Microvasc. Res [print-electronic]. 2010 Dec; 80(3): 295-302. PMID: 20553963, PMCID: PMC3390000, PII: S0026-2862(10)00132-9, DOI: 10.1016/j.mvr.2010.05.011, ISSN: 1095-9319.

Kim SJ, Toma HS, Barnett JM, Penn JS. Ketorolac inhibits choroidal neovascularization by suppression of retinal VEGF. Exp. Eye Res [print-electronic]. 2010 Oct; 91(4): 537-43. PMID: 20659449, PMCID: PMC3389996, PII: S0014-4835(10)00222-8, DOI: 10.1016/j.exer.2010.07.011, ISSN: 1096-0007.

Yanni SE, McCollum GW, Penn JS. Genetic deletion of COX-2 diminishes VEGF production in mouse retinal Müller cells. Exp. Eye Res [print-electronic]. 2010 Jul; 91(1): 34-41. PMID: 20398651, PMCID: PMC2879458, PII: S0014-4835(10)00108-9, DOI: 10.1016/j.exer.2010.03.019, ISSN: 1096-0007.

Williams C, Kim SH, Ni TT, Mitchell L, Ro H, Penn JS, Baldwin SH, Solnica-Krezel L, Zhong TP. Hedgehog signaling induces arterial endothelial cell formation by repressing venous cell fate. Dev. Biol [print-electronic]. 2010 May 5/1/2010; 341(1): 196-204. PMID: 20193674, PMCID: PMC3197743, PII: S0012-1606(10)00137-5, DOI: 10.1016/j.ydbio.2010.02.028, ISSN: 1095-564X.

Yanni SE, Clark ML, Yang R, Bingaman DP, Penn JS. The effects of nepafenac and amfenac on retinal angiogenesis. Brain Res. Bull [print-electronic]. 2010 Feb 2/15/2010; 81(2-3): 310-9. PMID: 19897019, PMCID: PMC2815002, PII: S0361-9230(09)00346-3, DOI: 10.1016/j.brainresbull.2009.10.018, ISSN: 1873-2747.

Recchia FM, Xu L, Penn JS, Boone B, Dexheimer PJ. Identification of genes and pathways involved in retinal neovascularization by microarray analysis of two animal models of retinal angiogenesis. Invest. Ophthalmol. Vis. Sci [print-electronic]. 2010 Feb; 51(2): 1098-105. PMID: 19834031, PMCID: PMC2868453, PII: iovs.09-4006, DOI: 10.1167/iovs.09-4006, ISSN: 1552-5783.

Barnett JM, McCollum GW, Penn JS. Role of cytosolic phospholipase A(2) in retinal neovascularization. Invest. Ophthalmol. Vis. Sci [print-electronic]. 2010 Feb; 51(2): 1136-42. PMID: 19661235, PMCID: PMC2868444, PII: iovs.09-3691, DOI: 10.1167/iovs.09-3691, ISSN: 1552-5783.

Barnett JM, Yanni SE, Penn JS. The development of the rat model of retinopathy of prematurity. Doc Ophthalmol [print-electronic]. 2010 Feb; 120(1): 3-12. PMID: 19639356, PMCID: PMC3752888, DOI: 10.1007/s10633-009-9180-y, ISSN: 1573-2622.

Yanni SE, Barnett JM, Clark ML, Penn JS. The role of PGE2 receptor EP4 in pathologic ocular angiogenesis. Invest. Ophthalmol. Vis. Sci [print-electronic]. 2009 Nov; 50(11): 5479-86. PMID: 19494202, PMCID: PMC4071769, PII: iovs.09-3652, DOI: 10.1167/iovs.09-3652, ISSN: 1552-5783.

Penn JS, Madan A, Caldwell RB, Bartoli M, Caldwell RW, Hartnett ME. Vascular endothelial growth factor in eye disease. Prog Retin Eye Res [print-electronic]. 2008 Jul; 27(4): 331-71. PMID: 18653375, PMCID: PMC3682685, PII: S1350-9462(08)00034-7, DOI: 10.1016/j.preteyeres.2008.05.001, ISSN: 1350-9462.

Berkowitz BA, Roberts R, Penn JS, Gradianu M. High-resolution manganese-enhanced MRI of experimental retinopathy of prematurity. Invest. Ophthalmol. Vis. Sci. 2007 Oct; 48(10): 4733-40. PMID: 17898298, PII: 48/10/4733, DOI: 10.1167/iovs.06-1516, ISSN: 0146-0404.

Barnett JM, McCollum GW, Fowler JA, Duan JJ, Kay JD, Liu RQ, Bingaman DP, Penn JS. Pharmacologic and genetic manipulation of MMP-2 and -9 affects retinal neovascularization in rodent models of OIR. Invest. Ophthalmol. Vis. Sci. 2007 Feb; 48(2): 907-15. PMID: 17251494, PMCID: PMC2614400, PII: 48/2/907, DOI: 10.1167/iovs.06-0082, ISSN: 0146-0404.

Werdich XQ, Penn JS. Specific involvement of SRC family kinase activation in the pathogenesis of retinal neovascularization. Invest. Ophthalmol. Vis. Sci. 2006 Nov; 47(11): 5047-56. PMID: 17065526, PII: 47/11/5047, DOI: 10.1167/iovs.05-1343, ISSN: 0146-0404.

Penn JS, McCollum GW, Barnett JM, Werdich XQ, Koepke KA, Rajaratnam VS. Angiostatic effect of penetrating ocular injury: role of pigment epithelium-derived factor. Invest. Ophthalmol. Vis. Sci. 2006 Jan; 47(1): 405-14. PMID: 16384991, PII: 47/1/405, DOI: 10.1167/iovs.05-0673, ISSN: 0146-0404.

Chen, J., Hicks, D., Brantley-Sieders, D., Cheng, N., McCollum, G.W., Werdich, X.Q. and Penn, J.S.. Inhibition of Retinal Neovascularization by Soluble EphA2 Receptor. Exp. Eye Res. 2006; 82(4): 664-73.

Kramerov A.A., Saghizadeh M., Pan H., Kabosova A., Montenarh M., Ahmed K., Penn J.S., Chan C.K., Hinton D.R., Grant M.B. and Ljubimov A.V.. Expression of protein kinase CK2 in astroglial cells of normal and neovascularized retina. Am J Pathol. 2006; 168(5): 1722-36.

Lutty G.A., Chan-Ling T., Phelps D.L., Adamis A.P., Berns K.I., Chan C.K., Cole C.H., D’Amore P.A., Das, A., Deng W-T., Dobson V., Flynn J.T., Friedlander M., Fulton A., Good W.V., Grant, M.B., Hansen R., Hauswirth W.V., Hardy R.J., Hinton D.R., Hughes S., McLeod D.S., Palmer E.A., Patz A., Penn J.S., Raisler B.J., Repka M.X., Saint-Geniez M., Shaw L.C., Shima D.T., Smith B.T., Smith L.E.H., Tahija S.G., Tasman W., Trese M.T.. Proceedings of the Third International Symposium on Retinopathy of Prematurity: An update on ROP from the lab to the nursery. Molecular Vision. 2006; 12: 532-80.

Werdich XQ, Penn JS. Src, Fyn and Yes play differential roles in VEGF-mediated endothelial cell events. Angiogenesis [print-electronic]. 2005; 8(4): 315-26. PMID: 16400523, DOI: 10.1007/s10456-005-9021-x, ISSN: 0969-6970.

Werdich XQ, McCollum GW, Rajaratnam VS, Penn JS. Variable oxygen and retinal VEGF levels: correlation with incidence and severity of pathology in a rat model of oxygen-induced retinopathy. Exp. Eye Res. 2004 Nov; 79(5): 623-30. PMID: 15500821, PII: S0014-4835(04)00199-X, DOI: 10.1016/j.exer.2004.07.006, ISSN: 0014-4835.

McCollum GW, Rajaratnam VS, Bullard LE, Yang R, Penn JS. Herbimycin A inhibits angiogenic activity in endothelial cells and reduces neovascularization in a rat model of retinopathy of prematurity. Exp. Eye Res. 2004 May; 78(5): 987-95. PMID: 15051479, PII: S0014483504000065, DOI: 10.1016/j.exer.2003.12.008, ISSN: 0014-4835.

York JR, Landers S, Kirby RS, Arbogast PG, Penn JS. Arterial oxygen fluctuation and retinopathy of prematurity in very-low-birth-weight infants. J Perinatol. 2004 Feb; 24(2): 82-7. PMID: 14762452, PII: 7211040, DOI: 10.1038/sj.jp.7211040, ISSN: 0743-8346.

Anderson, R.E. and Penn, J.S.. Environmental light and heredity provoke adaptive changes in retinal DHA levels that affect retinal function. Lipids. 2004; 39(11): 1121-4.

Penn JS, Rajaratnam VS. Inhibition of retinal neovascularization by intravitreal injection of human rPAI-1 in a rat model of retinopathy of prematurity. Invest. Ophthalmol. Vis. Sci. 2003 Dec; 44(12): 5423-9. PMID: 14638747, ISSN: 0146-0404.

Bullard LE, Qi X, Penn JS. Role for extracellular signal-responsive kinase-1 and -2 in retinal angiogenesis. Invest. Ophthalmol. Vis. Sci. 2003 Apr; 44(4): 1722-31. PMID: 12657614, ISSN: 0146-0404.

Penn JS, Rajaratnam VS, Collier RJ, Clark AF. The effect of an angiostatic steroid on neovascularization in a rat model of retinopathy of prematurity. Invest. Ophthalmol. Vis. Sci. 2001 Jan; 42(1): 283-90. PMID: 11133880, ISSN: 0146-0404.

Penn JS, Li S, Naash MI. Ambient hypoxia reverses retinal vascular attenuation in a transgenic mouse model of autosomal dominant retinitis pigmentosa. Invest. Ophthalmol. Vis. Sci. 2000 Nov; 41(12): 4007-13. PMID: 11053306, ISSN: 0146-0404.

Shafiee A, Roberts DD, Penn JS, Blake DA. Thrombospondin (TSP) peptides inhibit angiogenesis in retinal explant assay and rat model of retinopathy of prematurity. Invest. 2000; 41: 2378-88.

Berkowitz BA, Penn JS. Abnormal panretinal response pattern to carbogen inhalation in experimental retinopathy of prematurity. Invest. Ophthalmol. Vis. Sci. 1998 Apr; 39(5): 840-5. PMID: 9538894, ISSN: 0146-0404.

Berkowitz BA, Roberto KA, Penn JS. The vitreous protein concentration is increased prior to neovascularization in experimental ROP. Curr. Eye Res. 1998 Feb; 17(2): 218-21. PMID: 9523102, ISSN: 0271-3683.

Berkowitz BA, Lukaszew RA, Mullins CM, Penn JS. Impaired hyaloidal circulation function and uncoordinated ocular growth patterns in experimental retinopathy of prematurity. Invest. Ophthalmol. Vis. Sci. 1998 Feb; 39(2): 391-6. PMID: 9477999, ISSN: 0146-0404.

Robbins, S.G., Rajaratnam, V.S. and Penn, J.S. Evidence for upregulation and redistribution of vascular endothelial growth factor receptors flt-1 and flk-1 in the oxygen-injured rat retina. Growth Factors. 1998; 16: 1-9.

Berkowitz, B.A., R.A. Lukaszew, C.M. Mullins and J.S. Penn. Impaired hyaloidal circulation function and uncoordinated ocular growth patterns in experimental retinopathy of prematurity. Invest. Ophthalmol. Vis. Sci. 1998; 39((2)): 391-6.

Berkowitz, B.A., K.A. Roberto and J.S. Penn. The vitreous protein concentration is increased prior to neovascularization in experimental ROP. Curr. Eye Res. 1998; 17: 218-21.

Berkowitz, B.A. and J.S. Penn. Abnormal panretinal response pattern to carbogen inhalation in experimental retinopathy of prematurity. Invest. Ophthalmol. Vis. Sci. 1998; 39((5)): 838-43.

Robbins, S.G., Conaway, J.R., Tolman, B.L., Roberto, K.A. and Penn, J.S. Detection of vascular endothelial growth factor (VEGF) protein in vascular and non-vascular cells of the normal and oxygen-injured rat retina. Growth Factors. 1997; 14((4)): 279-95.

Niesman MR, Johnson KA, and Penn JS. Therapeutic effect of liposomal superoxide dismutase in an animal model of retinopathy of prematurity. Neurochem. Res. 1997; 22((5)): 597-605.

Kommonen, B.W., U. Karhunen, T. Kylma, W.W. Dawson and J.S. Penn. Impaired retinal function in young labrador retriever dogs heterozygous for late-onset rod-cone degeneration. Vis. Res. 1997; 37((3)): 365-70.

Penn, J.S., Tolman, B.L. and L.E. Bullard. Effect of a water soluble vitamin E analogue,Trolox, on retinal vascular development in an animal model of retinopathy of prematurity. Free Rad. Biol. Med. 1997; 22((6)): 977-84.

Penn, J.S. and M.M. Henry. Assessing retinal neovascularization in an animal model of proliferative retinopathy. Microvasc. Res. 1996; 51: 126-30.

Penn, J.S. and M.M. Henry. Evaluation of blood vessel assessment techniques in animals with retinal vascular disease. J. Ophthal. Phot. 1996; 18: 26-33.

Kommonen, B.W., T. Kylma, R.J. Cohen, J.S. Penn, L. Paulin, M.Y. Hurwitz and R.L. Hurwitz. Early changes in cyclic GMP levels and ultrastructure in photoreceptor degeneration in Labrador Retrievers. Ophthalmic Res. 1996; 28((1)): 19-28.

Roberto, K.A., B.L. Tolman and J.S. Penn. Long-term retinal vascular abnormalities in an animal model of retinopathy of prematurity. Cur. Eye Res. 1996; 15: 932-7.

Penn JS, Henry MM, Tolman BL and Wall PT. The range of PaO2 variation determines the severity of oxygen-induced retinopathy in newborn rats. Invest. Ophthalmol. Vis. Sci. 1995; (10)((36)): 2063-70.

Penn, J.S., B.L. Tolman, and M.M. Henry. Oxygen-induced retinopathy in the rat: relationship of retinal non-perfusion to subsequent neovascularization. 35Invest. Ophthalmol. Vis. Sci. 1994; (9): 3429-35.

Kommonen, B.W., J.S.Penn, T. Kylma, U. Karhunen, W.W. Dawson, B.L. Tolman, and T. Ukkola. Early morphometry of a retinal dystrophy in Labrador Retrievers. Acta Ophthalmologica. 1994; 72: 203-10.

Penn, J.S., M.M. Henry and B.L. Tolman. Exposure to alternating hypoxia and hyperoxia causes severe proliferative retinopathy in the newborn rat. Pediatr. Res. 1994; 36((6)): 724-31.

Penn, J.S., B.L. Tolman and L.A. Lowery. Variable oxygen exposure causes pre-retinal neovascularization in the newborn rat. Invest. Ophthalmol. Vis. Sci. 1993; 34((3)): 576-85.

Penn, J.S. and B.D. Johnson. Fluorescein angiography as a means of assessing retinal vascular pathology in oxygen-exposed newborn rats. Curr. Eye Res. 1993; 12((6)): 561-70.

Penn, J.S. and C.A. Gay. A new method of vascular analysis for animal models of retinopathy of prematurity. Exp. Eye Res. 1992; 54: 329-36.

Penn, J.S., L.A. Thum and M.I. Naash. Oxygen-induced retinopathy in the rat: Vitamins C and E as potential therapies. Invest. Ophthalmol. Vis. Sci. 1992; 33((6)): 1836-45.

Penn, J.S., B.L. Tolman, C.A. Koutz and L.A. Lowery. Oxygen-induced retinopathy in the rat: Hemorrhages and dysplasias may lead to retinal detachments. Cur. Eye Res. 1992; 11((10)): 939-53.

Penn, J.S., B.L. Tolman, L.A. Thum and C.A. Koutz. Effect of light history on the rat retina: Timecourse of morphological adaptation and readaptation. Neurochem. Res. 1991; 17((1)): 91-9.

Penn, J.S. Oxygen-induced retinopathy in the rat: Possible contribution of peroxidation reactions. Doc. Ophthalmol. 1990; 74: 179-86.

Larrazabal, L.I. and J.S. Penn. Fluorescein angiography in the newborn rat: Implications in oxygen-induced retinopathy. Invest. Ophthalmol. Vis. Sci. 1990; 31((5)): 810-8.

Williams, T.P., J.S. Penn, R.A. Bush, and C.L. Makino. Renewal of rod outer segments and regulation of daily photon catch by the rat retina. Pro. Yamada Conf. 1989; 255-60.

Penn, J.S. and L.A. Thum. Oxygen-induced retinopathy in the rat: Role of vitamin E in defending against peroxidation. Ann. N.Y. Acad. Sci. 1989; 495-7.

Penn, J.S., L.A. Thum and M.I. Naash. Photoreceptor physiology in the rat is governed by the light environment. Exp. Eye Res. 1989; 49((2)): 205-15.

Larrazabal, L.I. and J.S. Penn. Study of ocular vasculature in the newborn rat by fluorescein angiography. J. Ophthal. Phot. 1989; 11((2)): 49-52.

Penn, J.S., L.A. Thum, M. Rhem, and S.J. Dell. Effects of oxygen-rearing on the electroretinogram and GFA-protein in the rat. Invest. Ophthalmol. Vis. Sci. 1988; 29((11)): 1623-30.