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Guo J, Yang J, Huang H, Wu K, Wu X, Wang H, He Y, Bi F, Hu C, Gong B, Zhang H. A new mouse-fixation device for IOP measurement in awake mice. Vision Res 2024; 219:108397. [PMID: 38579406 DOI: 10.1016/j.visres.2024.108397] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2024] [Revised: 03/18/2024] [Accepted: 03/19/2024] [Indexed: 04/07/2024]
Abstract
Glaucoma is an irreversible blinding eye disease. The mechanisms underlying glaucoma are complex. Up to now, no successful remedy has been found to completely cure the condition. High intraocular pressure (IOP) is an established risk factor for glaucoma and the only known modifiable factor for glaucoma treatment. Mice have been widely used to study glaucoma pathogenesis. IOP measurement is an important tool for monitoring the potential development of glaucomatous phenotypes in glaucoma mouse models. Currently, there are two methods of IOP measurement in mice: invasive and non-invasive. As the invasive method can cause corneal damage and inflammation, and most of the noninvasive method involves the use of anesthetics. In the course of our research, we designed a mouse fixation device to facilitate non-invasive measurements of mouse IOPs. Using this device, mouse IOPs can be accurately measured in awake mice. This device will help researchers to accurately assess mouse IOP without the use of anesthetics.
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Affiliation(s)
- Jiaxin Guo
- The Key Laboratory for Human Disease Gene Study of Sichuan Province and Institute of Laboratory Medicine, Sichuan Provincial People's Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu 610072, China
| | - Jialiang Yang
- The Key Laboratory for Human Disease Gene Study of Sichuan Province and Institute of Laboratory Medicine, Sichuan Provincial People's Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu 610072, China
| | - Haotian Huang
- The Key Laboratory for Human Disease Gene Study of Sichuan Province and Institute of Laboratory Medicine, Sichuan Provincial People's Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu 610072, China
| | - Kai Wu
- School of Life Science and Technology, Center for Informational Biology, University of Electronic Science and Technology of China, Chengdu, China
| | - Xiawei Wu
- The Key Laboratory for Human Disease Gene Study of Sichuan Province and Institute of Laboratory Medicine, Sichuan Provincial People's Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu 610072, China
| | - Haolin Wang
- The Key Laboratory for Human Disease Gene Study of Sichuan Province and Institute of Laboratory Medicine, Sichuan Provincial People's Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu 610072, China
| | - Yu He
- The Key Laboratory for Human Disease Gene Study of Sichuan Province and Institute of Laboratory Medicine, Sichuan Provincial People's Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu 610072, China
| | - Fanfeng Bi
- The Key Laboratory for Human Disease Gene Study of Sichuan Province and Institute of Laboratory Medicine, Sichuan Provincial People's Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu 610072, China
| | - Chenyazhuo Hu
- The Key Laboratory for Human Disease Gene Study of Sichuan Province and Institute of Laboratory Medicine, Sichuan Provincial People's Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu 610072, China
| | - Bo Gong
- The Key Laboratory for Human Disease Gene Study of Sichuan Province and Institute of Laboratory Medicine, Sichuan Provincial People's Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu 610072, China; Institute of Chengdu Biology, Sichuan Translational Medicine Hospital, Chinese Academy of Sciences, Chengdu, Sichuan, China; Research Unit for Blindness Prevention of Chinese Academy of Medical Sciences (2019RU026), Sichuan Academy of Medical Sciences & Sichuan Provincial People's Hospital, Chengdu, Sichuan, China
| | - Houbin Zhang
- The Key Laboratory for Human Disease Gene Study of Sichuan Province and Institute of Laboratory Medicine, Sichuan Provincial People's Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu 610072, China; Research Unit for Blindness Prevention of Chinese Academy of Medical Sciences (2019RU026), Sichuan Academy of Medical Sciences & Sichuan Provincial People's Hospital, Chengdu, Sichuan, China.
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Atalay E, Altuğ B, Çalışkan ME, Ceylan S, Özler ZS, Figueiredo G, Lako M, Figueiredo F. Animal Models for Limbal Stem Cell Deficiency: A Critical Narrative Literature Review. Ophthalmol Ther 2024; 13:671-696. [PMID: 38280103 PMCID: PMC10853161 DOI: 10.1007/s40123-023-00880-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2023] [Accepted: 12/19/2023] [Indexed: 01/29/2024] Open
Abstract
This literature review will provide a critical narrative overview of the highlights and potential pitfalls of the reported animal models for limbal stem cell deficiency (LSCD) and will identify the neglected aspects of this research area. There exists significant heterogeneity in the literature regarding the methodology used to create the model and the predefined duration after the insult when the model is supposedly fully fit for evaluations and/or for testing various therapeutic interventions. The literature is also replete with examples wherein the implementation of a specific model varies significantly across different studies. For example, the concentration of the chemical, as well as its duration and technique of exposure in a chemically induced LSCD model, has a great impact not only on the validity of the model but also on the severity of the complications. Furthermore, while some models induce a full-blown clinical picture of total LSCD, some are hindered by their ability to yield only partial LSCD. Another aspect to consider is the nature of the damage induced by a specific method. As thermal methods cause more stromal scarring, they may be better suited for assessing the anti-fibrotic properties of a particular treatment. On the other hand, since chemical burns cause more neovascularisation, they provide the opportunity to tap into the potential treatments for anti-neovascularisation. The animal species (i.e., rats, mice, rabbits, etc.) is also a crucial factor in the validity of the model and its potential for clinical translation, with each animal having its unique set of advantages and disadvantages. This review will also elaborate on other overlooked aspects, such as the anaesthetic(s) used during experiments, the gender of the animals, care after LSCD induction, and model validation. The review will conclude by providing future perspectives and suggestions for further developments in this rather important area of research.
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Affiliation(s)
- Eray Atalay
- Department of Ophthalmology, Eskişehir Osmangazi University Medical School, Eskişehir, Turkey
| | - Burcugül Altuğ
- Cellular Therapy and Stem Cell Production Application, Research Centre (ESTEM), Eskişehir Osmangazi University, Eskişehir, Turkey
| | | | - Semih Ceylan
- Eskişehir Osmangazi University Medical School, Eskişehir, Turkey
| | | | | | - Majlinda Lako
- Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK
| | - Francisco Figueiredo
- Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK.
- Department of Ophthalmology, Royal Victoria Infirmary, Newcastle University, Newcastle upon Tyne, NE1 4LP, UK.
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Zheng YJ, Dilbeck MD, Economides JR, Horton JC. Permanent transduction of retinal ganglion cells by rAAV2-retro. Exp Eye Res 2024; 240:109793. [PMID: 38246331 DOI: 10.1016/j.exer.2024.109793] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2023] [Revised: 12/28/2023] [Accepted: 01/15/2024] [Indexed: 01/23/2024]
Abstract
Adeno-associated virus (AAV) is widely used as a vector for delivery of gene therapy. Long term therapeutic benefit depends on perpetual expression of the wild-type gene after transduction of host cells by AAV. To address this issue in a mass population of identified single cells, 4 rats received an injection of a 1:1 mixture of rAAV2-retro-hSyn-EGFP and rAAV2-retro-hSyn-mCherry into each superior colliculus. After the virus was transported retrogradely to both retinas, serial fundus imaging was performed at days 14, 45, 211, and 375 to visualize individual fluorescent ganglion cells. The location of each cell was plotted to compare labeling at each time point. In 12/16 comparisons, 97% or more of the cells identified in the initial baseline fundus image were still labeled at day 375. In 4 cases the percentage was lower, but in these cases the apparent reduction in the number of labeled cells at day 375 was attributable to the lower quality of follow-up fundus images, rather than true loss of transgene expression. These data indicate that retinal ganglion cells transduced by rAAV2-retro are transduced permanently.
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Affiliation(s)
- Yicen J Zheng
- Program in Neuroscience, Department of Ophthalmology University of California, San Francisco, San Francisco, CA, 94143, USA
| | - Mikayla D Dilbeck
- Program in Neuroscience, Department of Ophthalmology University of California, San Francisco, San Francisco, CA, 94143, USA
| | - John R Economides
- Program in Neuroscience, Department of Ophthalmology University of California, San Francisco, San Francisco, CA, 94143, USA
| | - Jonathan C Horton
- Program in Neuroscience, Department of Ophthalmology University of California, San Francisco, San Francisco, CA, 94143, USA.
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4
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Beckmann L, Cai Z, Margolis M, Fang R, Djalilian A, Zhang HF. Recent advances in optical coherence tomography for anterior segment imaging in small animals and their clinical implications. Ocul Surf 2022; 26:222-233. [PMID: 36195237 PMCID: PMC10040227 DOI: 10.1016/j.jtos.2022.08.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Revised: 08/16/2022] [Accepted: 08/17/2022] [Indexed: 12/05/2022]
Abstract
Anterior segment optical coherence tomography (AS-OCT) is a rapidly evolving area of OCT imaging, providing high-resolution and non-invasive volumetric imaging of the anterior segment. This review focuses on recent advances in AS-OCT imaging in small animals, which we categorize into ultrahigh-resolution, spectroscopic, magnetomotive, polarization-sensitive, and angiographic AS-OCTs. We summarize their technical foundations, review their applications to small animal imaging, and briefly discuss their current and future clinical applications.
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Affiliation(s)
- Lisa Beckmann
- Department of Biomedical Engineering, Northwestern University, Evanston IL, USA
| | - Zhen Cai
- Department of Biomedical Engineering, Northwestern University, Evanston IL, USA; Currently with Department of Ophthalmology, Tongji Medical College, HuaZhong University of Science and Technology, Wuhan, Hubei, China
| | - Mathew Margolis
- Department of Ophthalmology and Visual Science, University of Illinois at Chicago, Chicago IL, USA
| | - Raymond Fang
- Department of Biomedical Engineering, Northwestern University, Evanston IL, USA
| | - Ali Djalilian
- Department of Ophthalmology and Visual Science, University of Illinois at Chicago, Chicago IL, USA
| | - Hao F Zhang
- Department of Biomedical Engineering, Northwestern University, Evanston IL, USA.
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Kamio K, Morita J, Nakanishi Y, Sasaki M, Wakamatsu M. Corneal lesions related to an anesthetic mixture of medetomidine, midazolam, and butorphanol treatment in rats. J Toxicol Sci 2021; 46:561-568. [PMID: 34853242 DOI: 10.2131/jts.46.561] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
An anesthetic mixture of medetomidine, midazolam and butorphanol (MMB) has been recently used in laboratory animals. We observed corneal opacity in nephrectomized rats that had undergone two operations under MMB anesthesia at 4 and 5 weeks of age. To evaluate the features of this corneal opacity, ophthalmic examinations were conducted in 83 nephrectomized rats, and 8 representative animals with corneal opacity were evaluated histopathologically 4 weeks after operation. The ophthalmic examinations revealed that 66/83 animals had corneal opacity, which was characterized histopathologically by mineralization with or without inflammation in the corneal stroma. In addition, to examine the possible causes of this corneal opacity, we investigated whether similar corneal changes were induced by the MMB anesthetic treatment in normal rats. The MMB anesthetic was administered twice to 4- and 5-week-old normal SD rats (5 animals/age) in the same manner as for the nephrectomized rats. Ophthalmic examinations were conducted in all the animals once a week, and the animals were necropsied 4 weeks after the first administration. In normal rats, similar corneal opacity was observed after the first administration, and increases in the severity and size of the corneal opacity were noted after the second administration. In conclusion, this study revealed the features of corneal opacity in rats undergoing nephrectomy under MMB anesthesia and the occurrence of similar corneal opacity in normal rats treated with MMB anesthetic. To the best of our knowledge, this is the first report of corneal opacity related to MMB anesthetic treatment in rats.
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Affiliation(s)
- Kyohei Kamio
- Drug Safety and Pharmacokinetics Laboratories, Research Headquarters, Taisho Pharmaceutical Co., Ltd
| | - Junya Morita
- Drug Safety and Pharmacokinetics Laboratories, Research Headquarters, Taisho Pharmaceutical Co., Ltd
| | - Yutaka Nakanishi
- Drug Safety and Pharmacokinetics Laboratories, Research Headquarters, Taisho Pharmaceutical Co., Ltd
| | - Minoru Sasaki
- Senior Specialist Office, Pharmaceutical Product, Taisho Pharmaceutical Co., Ltd
| | - Masaki Wakamatsu
- Drug Safety and Pharmacokinetics Laboratories, Research Headquarters, Taisho Pharmaceutical Co., Ltd
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Damian DB, Ghiță AM, Istrate S, Coman IC. Experimental research in rats on the reactivity of new corneal blood vessels to adrenaline. Rom J Ophthalmol 2021; 65:64-69. [PMID: 33817436 PMCID: PMC7995500 DOI: 10.22336/rjo.2021.12] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/04/2021] [Indexed: 11/18/2022] Open
Abstract
Aim: The purpose of this experimental study was to evaluate the existence of adrenergic receptors in ketamine-induced corneal blood vessels in rat pups. Methods: The study of corneal neovascularization motricity was performed on 45-day-old Wistar rats in which, starting from the 15th day of life, corneal blood vessels were obtained by injecting intraperitoneal ketamine at a dose of 150 mg/ kg body weight, a total of 5 successive doses. The examination of the neovascularization was done with the help of a Nikon stereomicroscope connected to a video camera and a computer, the total magnification being 400X. The reactivity of the new corneal blood vessels to the administration in conjunctival instillations of a 1.5 mmol/L adrenaline solution was tested. The parameters followed were represented by variations in the caliber of corneal blood vessels. The data were analyzed using Microsoft Office Excel. Results: Administration of distilled water did not produce statistically significant changes in corneal blood vessels, while adrenaline produced a statistically significant constriction of vascular diameter (p=0.01 at T9, p=0.004 at T10, p=0.019 at time T11 of examinations). Conclusions: The results showed that adrenaline produces vasoconstriction in the new corneal blood vessels, which allows us to assume that they contain α-adrenergic receptors. However, we cannot say that corneal pathological vessels do not contain β2-type adrenergic receptors, because the effect of adrenaline may be an algebraic sum between vasoconstriction produced by stimulating α-adrenergic receptors and vasodilation produced by stimulating β2-adrenergic receptors, but in which the vasodilating effect may be masked by the vasoconstrictor effect given by a higher density of α-adrenergic receptors. Abbreviations: A= adrenaline, DNM = non-measurable diameter, NA= noradrenaline, Std.Er.= Standard error.
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Affiliation(s)
- Daniela Bianca Damian
- Department of Ophthalmology, “Dr. Alexandru Popescu” Military Emergency Hospital Focșani, Focșani, Vrancea, Romania
| | - Aurelian Mihai Ghiță
- Department of Physiology, “Carol Davila” University of Medicine and Pharmacy, Bucharest, Romania
| | - Sânziana Istrate
- Department of Ophthalmology, “Carol Davila” University of Medicine and Pharmacy, Bucharest, Romania
| | - Ioana Cristina Coman
- Department of Ophthalmology, “Carol Davila” University of Medicine and Pharmacy, Bucharest, Romania
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7
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Zwick LS, Patrick DJ, Knupp LC, Ramos MF. Ketamine/Xylazine Anesthesia-Related Corneal Lesions in Rats With Surgically Implanted Venous Catheters Utilized in Nonclinical Intravenous Studies. Toxicol Pathol 2020; 49:598-601. [PMID: 33043871 DOI: 10.1177/0192623320960705] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Nonclinical rodent studies with repeat slow intravenous dosing, such as safety assessments of anticancer therapeutics, often require the use of animals with surgically implanted catheters. Catheterization is a relatively short surgical procedure but requires use of anesthesia. Ketamine/xylazine injectable anesthesia is typically used because it has advantages over inhalation anesthesia including ease of administration, safety and predictability of effects, and relatively low cost. However, ketamine/xylazine anesthesia in rodents can also be associated with the development of undesirable corneal lesions of uncertain mechanism such as mineralization of Bowman's membrane or stroma, erosion/ulceration, inflammation, fibroplasia, and neovascularization. Such findings have the potential to confound study interpretation in programs for which the cornea is a potential target tissue. This case report describes the occurrence of ketamine/xylazine-related corneal lesions observed in surgically catheterized rats in a 16-day toxicity study for an oncology compound.
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Abstract
Purpose We have observed that the commonly used ketamine/xylazine anesthesia mix can induce a focally severe and permanent corneal opacity. The purpose of this study was to establish the clinical and histological features of this deleterious side effect, its sensitivity with respect to age and anesthesia protocol, and approaches for avoiding it. Methods Young C57BL/6J, C57BLKS/J, and SJL/J mice were treated with permutations of anesthesia protocols and compared using slit-lamp exams, optical coherence tomography, histologic analyses, and telemetric measurements of body temperature. Results Ketamine/xylazine induces corneal damage in mice with a variable frequency. Among 12 experimental cohorts, corneal damage associated with ketamine/xylazine was observed in 9 of them. Despite various treatments to avoid corneal dehydration during anesthesia, the frequency of corneas experiencing damage among responding cohorts was 42% (26% inclusive of all cohorts), which is significantly greater than the natural prevalence (5%). The damage was consistent with band keratopathy. It appeared as a white or gray horizontal band located proximal to the pupil and was positive for subepithelial calcium deposition with von Kossa stain. Conclusions The sum of our clinical and histological observations is consistent with ketamine/xylazine-induced band keratopathy in mice. This finding is relevant for mouse studies involving the eye and/or vision-dependent behavioral assays, which would both be prone to artifact without appreciation of the damage caused by ketamine/xylazine anesthesia. Use of yohimbine is suggested as a practical means of avoiding this complication.
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Xiao YF, Wang B, Wang X, Du F, Benzinou M, Wang YXJ. Xylazine-induced reduction of tissue sensitivity to insulin leads to acute hyperglycemia in diabetic and normoglycemic monkeys. BMC Anesthesiol 2013; 13:33. [PMID: 24138083 PMCID: PMC4016475 DOI: 10.1186/1471-2253-13-33] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2013] [Accepted: 10/15/2013] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND The α2-adrenoceptor agonist xylazine as an anesthetic has been widely used either alone or in combination with other anesthetics, such as ketamine, in veterinary clinic and research. In the last decade xylazine has been used in drug abusers in certain geographic area. This study investigated the effects of xylazine on blood glucose level and insulin secretion in normoglycemic and insulin-dependent diabetic monkeys. METHODS Both adult cynomolgus (n = 10) and rhesus (n = 8) monkeys with either sex were used in the study. Xylazine (1-2 mg/kg) was administrated intramuscularly. Blood glucose, insulin, glucagon and glucagon-like peptide 1 in overnight-fasted monkeys were measured immediately before and after xylazine administration. The hyperinsulinemic-euglycemic clamp method was used in the study for assessing the potential mechanism of xylazine-induced hyperglycemia. RESULTS Xylazine administration increased the blood glucose levels from 58 ± 3 to 108 ± 12 mg/dL in normoglycemic (n = 5, p < 0.01) and from 158 ± 9 to 221 ± 13 mg/dL in insulin-dependent diabetic (n = 5, p < 0.01) monkeys and was not accompanied by any significant changes in blood insulin, glucagon, and glucagon-like peptide-1. Xylazine-induced hyperglycemia occurred within 10 min and reached the peak at 35 min after injection. Xylazine-induced hyperglycemia declined slowly in diabetic animals. The α2-adrenoceptor antagonist yohimbine was administrated to bring down the elevated glucose level to the pre-xylazine one in 4 out of 5 diabetic animals. To assess the potential mechanism, the hyperinsulinemic-euglycemic clamp was used to maintain a nearly saturated and constant insulin level for minimizing endogenous insulin glucoregulation. Xylazine administration decreased glucose infusion rate, from 14.3 ± 1.4 to 8.3 ± 0.8 mg/min/kg (n = 6, p < 0.01) in normoglycemic rhesus monkeys, which indicates that the glucose metabolic rate (M rate) was decreased by xylazine. In addition, after clamping blood glucose level in a range of 55 to 75 mg/dL for 40 min with constant glucose infusion, xylazine administration still increased blood glucose concentration. CONCLUSIONS We conclude that xylazine administration induces hyperglycemia in normoglycemic and insulin-dependent diabetic monkeys potentially via stimulation of α2-adrenoceptors and then reducing tissue sensitivity to insulin and glucose uptake.
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Affiliation(s)
- Yong-Fu Xiao
- Cardiovascular and Metabolic Disease Research, Crown Bioscience Inc, Science and Technology Park, 6 Beijing West Road, Taicang Economic Development Area, Jiangsu Province 215400, The People's Republic of China.
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Rosolen SG, Lamory B, Harms F, Sahel JA, Picaud S, LeGargasson JF. Cellular-resolution in vivo imaging of the feline retina using adaptive optics: preliminary results. Vet Ophthalmol 2011; 13:369-76. [PMID: 21182721 DOI: 10.1111/j.1463-5224.2010.00829.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE To perform cellular-level in vivo imaging of the feline retina using an adaptive optics flood illumination fundus camera (AO FIFC) designed for the human eye. MATERIALS AND METHODS Cellular-level images were obtained from three eyes of two normal sedated cats. Ocular aberrations were corrected using an AO system based on a 52-acuator electromagnetic deformable mirror and a 1024 lenslet Hartmann-Shack sensor (both Imagine Eyes, Orsay, France). A square 3°×3° area of the ocular fundus was flood-illuminated by a pulsed LED emitting at 850 nm and imaged onto a low-noise, high-resolution CCD camera. The animal's pupils were dilated and the effective pupil size was set to 7.5 mm. Conjunctival atraumatic clips were used to avoid eyeball movements and eyelid closure. The cornea was artificially hydrated throughout the experiments. Each acquisition consisted of 20 consecutive images, out of which 10 were numerically averaged to produce an enhanced final image. RESULTS The total amount of ocular aberrations was greatly reduced by the AO correction, from 2.4 to 0.21 microns root mean square on average. The resulting images presented white dots distributed at a density similar to that of cone photoreceptors and they allowed us to visualize small blood vessels and nerve fiber bundles at a higher resolution than classically obtained with conventional fundus photography. CONCLUSION Retinal imaging with cellular resolution was feasible in cats under sedation using an AO FIFC designed for human eyes without any optical modification. The AO FIFC technology could find new applications in clinical, pharmacological, and toxicological investigations.
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Affiliation(s)
- Serge G Rosolen
- Clinique Veterinaire Voltaire, 119 Boulevard Voltaire, Asnières, France
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Papp AM, Nyilas R, Szepesi Z, Lorincz ML, Takács E, Abrahám I, Szilágyi N, Tóth J, Medveczky P, Szilágyi L, Juhász G, Juhász G. Visible light induces matrix metalloproteinase-9 expression in rat eye. J Neurochem 2007; 103:2224-33. [PMID: 17854381 DOI: 10.1111/j.1471-4159.2007.04917.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Up-regulation of matrix metalloproteinase-9 (MMP-9, gelatinase B) in the nervous system has been demonstrated when excitotoxicity-induced tissue remodeling and neuronal death occurs. Induction of MMP-9 by a natural stimulus has not been observed yet. Using RT-PCR and gelatin-zymography we demonstrated MMP-9 induction at transcriptional and protein levels in different structures of the rat eye following over-stimulation with white light. MMP-9 elevation occurred in the retina without reduction in photoreceptor number or major anatomical reorganization. A transient decrease in electroretinogram b-wave indicated the functional recovery. Retrobulbar injection of a broad-spectrum MMP-inhibitor GM6001, slowed the recovery rate of b-wave amplitude. Even room-light applied to dark-adapted awake animals induced MMP-9 increase in the retina, which suggests a role for MMP-9 in physiological functional plasticity of the nervous system, such as light adaptation. This is the first demonstration of MMP-9 induction by a sensory stimulus.
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MESH Headings
- Adaptation, Ocular/drug effects
- Adaptation, Ocular/physiology
- Adaptation, Ocular/radiation effects
- Animals
- Dark Adaptation/drug effects
- Dark Adaptation/physiology
- Dark Adaptation/radiation effects
- Enzyme Induction/radiation effects
- Enzyme Inhibitors/pharmacology
- Light
- Male
- Matrix Metalloproteinase 9/genetics
- Matrix Metalloproteinase 9/metabolism
- Matrix Metalloproteinase 9/radiation effects
- Membrane Potentials/drug effects
- Membrane Potentials/physiology
- Membrane Potentials/radiation effects
- Neuronal Plasticity/drug effects
- Neuronal Plasticity/physiology
- Neuronal Plasticity/radiation effects
- Photic Stimulation
- RNA, Messenger
- Rats
- Rats, Sprague-Dawley
- Retina/drug effects
- Retina/enzymology
- Retina/radiation effects
- Stress, Physiological/enzymology
- Stress, Physiological/etiology
- Stress, Physiological/physiopathology
- Vision, Ocular/drug effects
- Vision, Ocular/physiology
- Vision, Ocular/radiation effects
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Affiliation(s)
- Andrea M Papp
- Laboratory of Proteomics, Institute of Biology, Eötvös Loránd University, Budapest, Hungary
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Federici L, Proust H, Conrath J, Ridings B. [Bilateral corneal endothelial decompensation after postsepticemia coma]. J Fr Ophtalmol 2006; 29:556-8. [PMID: 16885831 DOI: 10.1016/s0181-5512(06)73810-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
We report a case of unexplained bilateral corneal endothelial decompensation after a coma. A 71-year-old man with no medical history presented with bilateral endothelial decompensation that required penetrating keratoplasty of the left eye combined with cataract surgery. This coma was caused by septicemia originally due to staphylococcus infection following catheter placement in preparation for a CT scan. Visual acuity of the left eye was 20/400 and 20/100 in the right eye when the patient awoke from the coma. After examination, we noted only stromal thickening and Descemet membrane folds causing corneal edema predominating OS. The rest of the exam was normal. Six months after surgery, visual acuity improved to 20/25. The most probable physiopathological mechanism of this decompensation is an iatrogenic complication from drugs administered during the patient's stay in intensive care (oxacillin), but we cannot rule out direct aggression of a bacterium or its toxin or the decompensation of a preexisting pathology.
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Affiliation(s)
- L Federici
- Service d'Ophtalmologie, Hôpital La Timone, Marseille
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