1.Electroretinogram and histopathologic changes of the retina after methanol intoxication.
Jie-Min CHEN ; Guang-You ZHU ; Zi-Qin ZHAO ; Wen-Tao XIA
Journal of Forensic Medicine 2013;29(1):5-16
In order to study the functional and structural alterations of the retina in SD rat model after methanol intoxication, 35 rats were divided randomly into five groups administrated with saline, 3-day high dose, 7-day high dose, 3-day low dose and 7-day low dose methanol separately. The retinal function of each group was assessed by flash electroretinogram (F-ERG) 3 and 7 days after methanol poisoning. The microstructure and ultrastructure of the retina were observed at the same time. The high-dose methanol intoxication induced irreversible retinal functional and structural damages 3 days after poisoning, which included prolonged latency and reduced amplitude of the Max-reaction of F-ERG. These injuries were aggravated 7 days after poisoning. Meanwhile, the latency and amplitude of the Cone-reaction of F-ERG were also affected 3 days after poisoning, but there were no further worsening tendency 7 days after poisoning. The retinal histological analysis showed cellular edema, heteromorphy and disarrangement, tissular loosen of the inner nuclear layer and photoreceptors layer. The mitochondrial damage began at the photoreceptors layer and developed further into the inner nuclear layer. The low-dose methanol intoxication only caused transient damage of the retina. Our results showed that the function and structure of the photoreceptor and inner nuclear layer were the primary target of methanol intoxication and that the rod cells were more sensitive to methanol intoxication than the cone cells. The mitochondrial damage developed from outer layer to inner layer of the retina.
Animals
;
Edema/pathology*
;
Electroretinography
;
Forensic Medicine
;
Male
;
Methanol/poisoning*
;
Mitochondria/pathology*
;
Photoreceptor Cells/pathology*
;
Random Allocation
;
Rats
;
Rats, Sprague-Dawley
;
Retina/physiopathology*
;
Retinal Cone Photoreceptor Cells/pathology*
;
Retinal Diseases/pathology*
;
Retinal Rod Photoreceptor Cells/pathology*
;
Time Factors
2.The effect of Vaccinium uliginosum on rabbit retinal structure and light-induced function damage.
Lan YIN ; Yu-Li PI ; Mao-Nian ZHANG
Chinese journal of integrative medicine 2012;18(4):299-303
OBJECTIVETo study the effect of Vaccinium uliginosum L., (VU) on the electroretinogram (ERG) and retinal pathological changes in rabbits after light-induced damage.
METHODSTwenty-eight Chinchilla rabbits were randomly divided into four groups: administration beforehand (A), administration after injury (B), light injury without administration (C), and blank (D) groups. After a 4-week administration of VU homogenate at 4.8 g/(kg·d) once a day in group A, ERG in groups A, B and C were recorded according to the standards set by the International Society for Clinical Electrophysiology of Vision (ISCEV). Except for group D, the groups were then exposed to strong light. Just after that, group A stopped receiving VU treatment and group B started to receive it. Then ERGs in all groups were recorded after 1 day, 1 week, and 2 weeks. Throughout the whole process groups which were not fed with VU were fed with normal saline. Finally, the tissues and structures of all the groups were observed and the thickness of the outer nuclear layers (ONL) was measured.
RESULTS(1) After 4-week feeding with VU, the latency time of ERG in group A became shorter than those in the other groups and the amplitude increased. After being exposed to strong light, the latency time lengthened and amplitude decreased in all the injury groups, but comparing at each time point, the measured values in group A were better than those in group C. With the accumulation of VU, the ERG in group B improved, and finally, all of the detected values became better than those in group C. (2) Retinae in group D were normal in histology and the layers were in order but those in group C became disarranged. The injuries in groups A and B were minor compared with those in group C. The thickness of the ONL in group C was significantly thinner than in the other groups (P=0.000), and that in groups A and B was thicker than that in group C, although thinner than in group D. That in group A was thicker than in group B.
CONCLUSIONSVU can relieve the injury to rabbit retinae exposed to normal day and night rhythm, alleviate the harm caused by light when used beforehand, and repair the light damage to the retina.
Animals ; Electroretinography ; Light ; Plant Extracts ; pharmacology ; Rabbits ; Retina ; drug effects ; pathology ; physiopathology ; radiation effects ; Retinal Cone Photoreceptor Cells ; drug effects ; pathology ; radiation effects ; Retinal Rod Photoreceptor Cells ; drug effects ; pathology ; radiation effects ; Time Factors ; Vaccinium ; chemistry
3.Restraining effects of acupuncture on photoreceptor cell apoptosis in rats with retinitis pigmentosa induced by N-methyl-N-nitrosourea.
Rui-ling MA ; Guo-min ZHOU ; Ren ZHANG
Chinese Journal of Integrated Traditional and Western Medicine 2009;29(1):43-45
OBJECTIVETo observe the effect of acupuncture on photoreceptor cell apoptosis in rats with retinitis pigmentosa induced by N-methyl-N-nitrosourea (MNU).
METHODSFifty-day-old female SD rats were established into model of retinitis pigmentosa by once intraperitoneal injection of 50 mg/kg MNU, and randomly grouped to the acupuncture group and the model group for observing the cell apoptosis in rats and compared with that in normal rats at the corresponding time points.
RESULTSAcupuncture showed no effect on cell apoptosis at its peak of occurring, apoptotic phenomena still could be seen on days 5 and 7, but it was significantly less in the acupuncture group than in the model group (P < 0.01). Moreover, acupuncture showed a restraining effect on the up-regulation of caspase-3 activity.
CONCLUSIONAcupuncture can restrain the MNU induced apoptosis of photoreceptor cells, the effect is correlated, to a certain degree, with the status of the apoptosis occurrence.
Acupuncture Therapy ; Animals ; Apoptosis ; physiology ; Caspase 3 ; metabolism ; Female ; Methylnitrosourea ; Photoreceptor Cells ; pathology ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Retinitis Pigmentosa ; chemically induced ; therapy
4.Characterization of Peripapillary Atrophy Using Spectral Domain Optical Coherence Tomography.
Jung Hwa NA ; Byung Gil MOON ; Kyung Rim SUNG ; Youngrok LEE ; Michael S KOOK
Korean Journal of Ophthalmology 2010;24(6):353-359
PURPOSE: To characterize the features of peripapillary atrophy (PPA), as imaged by spectral-domain optical coherence tomography (SD-OCT). METHODS: SD-OCT imaging of the optic disc was performed on healthy eyes, eyes suspected of having glaucoma, and eyes diagnosed with glaucoma. From the peripheral beta-zone, the retinal nerve fiber layer (RNFL), the junction of the inner and outer segments (IS/OS) of the photoreceptor layer, and the Bruch's membrane/retinal pigment epithelium complex layer (BRL) were visualized. RESULTS: Nineteen consecutive eyes of 10 subjects were imaged. The RNFL was observed in the PPA beta-zone of all eyes, and no eye showed an IS/OS complex in the beta-zone. The BRL was absent in the beta-zone of two eyes. The BRL was incomplete or showed posterior bowing in the beta-zone of five eyes. CONCLUSIONS: The common findings in the PPA beta-zone were that the RNFL was present, but the photoreceptor layer was absent. Presence of the BRL was variable in the beta-zone areas.
Adult
;
Aged
;
Bruch Membrane/pathology
;
Female
;
Glaucoma/*complications
;
Humans
;
Male
;
Middle Aged
;
Nerve Fibers/pathology
;
Optic Atrophy/*diagnosis/*etiology
;
Optic Disk/*pathology
;
Photoreceptor Cells, Vertebrate/pathology
;
Retina/pathology
;
Retinal Pigment Epithelium/pathology
;
Tomography, Optical Coherence/*methods
5.Protective effects of ligustrazine against photoreceptor cell injury induced by N-methyl-N-nitrosourea and its mechanism.
Jin-nan YANG ; Jian-gong XU ; Jin-mao CHEN ; Shao-chun LIN ; Lin LUO ; Shi-xing HU
Acta Pharmaceutica Sinica 2005;40(8):690-694
AIMTo study the protective effect of ligustrazine against photoreceptor cell injury induced by N-methyl-N-nitrosourea (MNU) in Sprague-Dawley (SD) rats.
METHODSLigustrazine injections of different doses were injected intraperitoneally into 47-day female SD rats once a day and a single intraperitoneal injection of MNU 60 mg x kg(-1) was given to 50-day rats. At different intervals after MNU treatment,the animals were sacrificed. The apoptotic index of photoreceptor cells was calculated by TUNEL labeling at 24 h following MNU treatment; peripheral retinal damage was evaluated based on retinal thickness at the d 7 after MNU treatment, and the expression of c-jun and c-fos genes was detected by RT-PCR technique.
RESULTSLigustrazine injection could remarkably increase total thickness of peripheral retina and decrease apoptotic index of photoreceptor cells induced by MNU in a dose-dependent manner. Compared with MNU-treated rats, the gene expression of c-jun and c-fos was time-dependently down-regulated in ligustrazine-treated group.
CONCLUSIONLigustrazine injection partially protects against MNU-induced retinal damage by down-modulating the expression of c-jun and c-fos genes to inhibit apoptosis of photoreceptor cells.
Animals ; Apoptosis ; drug effects ; Dose-Response Relationship, Drug ; Female ; Genes, fos ; Genes, jun ; Injections, Intraperitoneal ; Ligusticum ; chemistry ; Methylnitrosourea ; Photoreceptor Cells ; drug effects ; Photoreceptor Cells, Vertebrate ; drug effects ; pathology ; Plants, Medicinal ; chemistry ; Protective Agents ; administration & dosage ; pharmacology ; Pyrazines ; administration & dosage ; isolation & purification ; pharmacology ; Rats ; Rats, Sprague-Dawley ; Retina ; metabolism ; pathology
6.Edema of the Photoreceptor Layer in Vogt-Koyanagi-Harada Disease Observed Using High-Resolution Optical Coherence Tomography.
Ji Eun LEE ; Seung Who PARK ; Ja Kyun LEE ; Hee Young CHOI ; Boo Sup OUM ; Hyun Woong KIM
Korean Journal of Ophthalmology 2009;23(2):74-79
PURPOSE: To evaluate the characteristics of fluid accumulation in the uveitic stage of Vogt-Koyanagi-Harada (VKH) disease using high resolution optical coherence tomography (OCT3). METHODS: Twenty-eight eyes in 14 patients with VKH disease were reviewed retrospectively. These 28 eyes were divided into 19 eyes with intraretinal fluid (C group) and 9 eyes without intraretinal fluid (N group). Changes in visual acuity and fluid accumulation observed using OCT were compared between the two groups. RESULTS: Visual acuity at the time of presentation was significantly worse in the C group than in the N group (p=0.005). The photoreceptor layer appeared to be double-layered due to a cystoid space in the C group. Layered structures and strands found in the cystoid space. Expanding sponge-form edema led to the development of a cystoid space in the photoreceptor layer. Intraretinal fluid resolved earlier than subretinal fluid. There were no observed differences in visual acuity between the two groups after four days of treatment. CONCLUSIONS: Accumulation of intraretinal fluid was related to poor initial visual acuity, but not to final visual acuity. High resolution OCT findings indicate that edema of the photoreceptor layer participates in the development of a cystoid space.
Adolescent
;
Adult
;
Diagnosis, Differential
;
Female
;
Follow-Up Studies
;
Humans
;
*Image Enhancement
;
Macular Edema/etiology/*pathology
;
Male
;
Middle Aged
;
Photoreceptor Cells, Vertebrate/*pathology
;
Retrospective Studies
;
Tomography, Optical Coherence/*methods
;
Uveomeningoencephalitic Syndrome/*complications/pathology
;
Young Adult
7.Central Photoreceptor Viability and Prediction of Visual Outcome in Patients with Idiopathic Macular Holes.
Song Ee CHUNG ; Dong Hui LIM ; Se Woong KANG ; Young Hee YOON ; Ju Byung CHAE ; In Ho ROH
Korean Journal of Ophthalmology 2010;24(4):213-218
PURPOSE: To identify the correlation between preoperative optical coherence tomography (OCT) features and postoperative visual outcomes in eyes with idiopathic macular holes (MHs). METHODS: Data from 55 eyes with idiopathic MHs which had been sealed by vitrectomy were retrospectively reviewed. Correlation analysis was conducted between postoperative visual acuity (V(postop), logarithm of the minimum angle of resolution [logMAR]) and preoperative factors, including four OCT parameters: the anticipated length (A) devoid of photoreceptors after hole closure, MH height (B), MH size (C), and the grading (D) of the viability of detached photoreceptors. Additionally, the formula for the prediction of visual outcome was deduced. RESULTS: V(postop) was determined to be significantly correlated with the preoperative visual acuity (V(preop)) and OCT parameters A, C, and D (p<0.001). Based on the correlation, the formula for the prediction of V(postop) was derived from the most accurate regression analysis: V(postop)=0.248xV(preop)+1.1x10(-6)xA(2)-0.121xD+0.19. CONCLUSIONS: The length and viability of detached photoreceptors are significant preoperative OCT features for predicting visual prognosis. This suggests that, regardless of the MH size and symptom duration, active surgical intervention should be encouraged, particularly if the MH exhibits good viability in the detached photoreceptor layer.
Cell Survival
;
Female
;
Follow-Up Studies
;
Humans
;
Male
;
Middle Aged
;
Photoreceptor Cells, Vertebrate/*pathology
;
Prognosis
;
Retinal Perforations/*pathology/physiopathology/surgery
;
Retrospective Studies
;
Tomography, Optical Coherence
;
Visual Acuity/*physiology
;
Vitrectomy/methods
8.Morphologic Characteristics of the Outer Retina in Cone Dystrophy on Spectral-domain Optical Coherence Tomography.
Soo Chang CHO ; Se Joon WOO ; Kyu Hyung PARK ; Jeong Min HWANG
Korean Journal of Ophthalmology 2013;27(1):19-27
PURPOSE: To investigate the morphologic changes in the outer retina of patients with cone dystrophy, using spectral-domain optical coherence tomography (SD-OCT). METHODS: The medical records of 15 cone dystrophy patients examined from January 2007 to January 2012 were reviewed retrospectively. All patients underwent ophthalmic evaluation including best-corrected visual acuity (BCVA), color vision testing, fundus examination, full-field standard electroretinography (ERG), multifocal (mf) ERG, and SD-OCT. Qualitative and quantitative SD-OCT data and ERG responses were analyzed and compared among the patient categories and the normal control group. RESULTS: There were 4 major categories of SD-OCT findings, based on the status of the ellipsoid portion of the photoreceptor inner segment (ISe), outer segment (OS) contact cylinder, and retinal pigment epithelium (RPE) layer. Category 0 showed no structural abnormalities. Category 1 showed foveal ISe loss and obscurity of the border between the ISe band and the external limiting membrane (ELM). Category 2 showed foveal thinning and focal foveal ISe disruption with an intact ELM. Category 3 showed foveal thickening and perifoveal disruption of the ISe layer. Category 1 to 3 showed OS contact cylinder layer absence and RPE thickening. The patients in category 0 tended to be younger (mean, 10.0 years) than those in categories 1 to 3 (mean, 17.6 years), although this difference was not statistically significant. Category 1 to 3 patients exhibited statistically significant thinning of the central retina and outer nuclear layer and thickening of the RPE layer relative to the category 0 and normal control group. There was a significant correlation between the central foveal thickness and BCVA in the patients with cone dystrophy. ERG and mfERG responses did not differ significantly among the different cone dystrophy categories. CONCLUSIONS: The morphologic features of cone dystrophy as revealed by SD-OCT, could be categorized as either normal or 1 of 3 different types of outer retinal changes. The presence of normal retinal structures in young cone dystrophy patients with functional impairment (category 0) indicates that electrophysiologic studies are superior to current imaging modalities for the early diagnosis of cone dystrophy. The characteristic SD-OCT findings in cone dystrophy patients may aid in differential diagnosis and be useful for future research on the pathology of cone dystrophy.
Adolescent
;
Adult
;
Child
;
Child, Preschool
;
Electroretinography
;
Female
;
Fluorescein Angiography
;
Fundus Oculi
;
Humans
;
Male
;
Middle Aged
;
Ophthalmoscopy
;
Reproducibility of Results
;
Retinal Cone Photoreceptor Cells/*pathology
;
Retinal Dystrophies/*pathology/physiopathology
;
Retrospective Studies
;
Tomography, Optical Coherence/*methods
;
Visual Acuity
;
Young Adult
9.N-methyl-N-nitrosourea-induced apoptosis of photoreceptor cells in Sprague-Dawley rats via nuclear factor-kappaB.
Jin-nan YANG ; Lin LUO ; Shao-chun LIN ; Jin-mao CHEN ; Dai LI ; Shi-xing HU
Chinese Medical Journal 2005;118(13):1081-1086
BACKGROUNDPrevious studies have showed that photooxidative stress can lead to down-modulation of nuclear factor-kappa B (NF-kappaB) activity causing apoptosis of cultured photoreceptor cells. This study aimed at investigating whether NF-kappaB was involved in photoreceptor cells apoptosis induced by N-methyl-N-nitrosourea (MNU) in rats.
METHODSA single intraperitoneal injection of 60 mg/kg MNU was given to 50-day-old female rats. At different intervals after MNU treatment, the animals were sacrificed. Retinal damage was examined by a light microscope. The apoptotic index of the photoreceptor cells was detected by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling (TUNEL). NF-kappaB was analysed by Western blot and Transcriptin Factor Assay Kits.
RESULTSThe pyknosis of the photoreceptor nuclei and the disorientation of the outer segment of the photoreceptor layer was seen after MNU treatment for 24 hours. The outer nuclear layer and photoreceptor layer were almost completely lost at 7 days. Photoreceptor cells apoptosis reached the peaked value at 24 hours. In apoptotic cascade, the protein levels of NF-kappaB p65 were only detected after MNU treatment for 12 and 24 hours in the nucleus. Conversely, the amounts of IkappaBalpha were markedly increased in the cytoplasm as well as in the nucleus. The activity of NF-kappaB p65 in the nucleus was down-modulated in the end.
CONCLUSIONSMNU-induced photoreceptor cell destruction was attributed to the apoptotic process by down-regulating the activation of NF-kappaB p65.
Animals ; Apoptosis ; drug effects ; Cell Nucleus ; metabolism ; Female ; I-kappa B Proteins ; analysis ; physiology ; Methylnitrosourea ; toxicity ; NF-KappaB Inhibitor alpha ; NF-kappa B ; analysis ; physiology ; Photoreceptor Cells ; chemistry ; drug effects ; pathology ; Rats ; Rats, Sprague-Dawley ; Retina ; drug effects ; pathology
10.Photoreceptor Disruption Related to Persistent Submacular Fluid after Successful Scleral Buckle Surgery.
Se Joon WOO ; Kyoung Min LEE ; Hum CHUNG ; Kyu Hyung PARK
Korean Journal of Ophthalmology 2011;25(6):380-386
PURPOSE: To investigate serial changes in photoreceptor status and associated visual outcome in patients with persistent submacular fluid after successful scleral buckle surgery for macula-off rhegmatogenous retinal detachment. METHODS: This was a prospective observational case series including 76 consecutive patients who underwent successful scleral buckle surgery for macula-off rhegmatogenous retinal detachment with symptom duration < or =90 days at a single tertiary hospital. Optical coherence tomography (OCT) and visual acuity examination were performed at one month and three months postoperatively and at three-month intervals until the submacular fluid disappeared. Main outcome measures were postoperative photoreceptor status on OCT and visual acuity. RESULTS: Forty-two patients (55.3%) showed persistent submacular fluid at postoperative one month. Of 42 patients with persistent submacular fluid, three (7.1%) showed photoreceptor disruption on OCT. None of the 34 patients without persistent submacular fluid showed photoreceptor disruption. Two patients (4.8%) had progressive photoreceptor disruption, and one patient (2.4%) had early photoreceptor disruption. All three patients showed photoreceptor reappearance and limited visual restoration after absorption of submacular fluid. Final visual acuities were significantly worse in these three patients (20 / 1000, 20 / 133, and 20 / 133) compared to those of the other patients (mean, 20 / 30) with persistent submacular fluid and intact photoreceptors. CONCLUSIONS: Even after successful scleral buckle surgery for rhegmatogenous retinal detachment, photoreceptor disruption can occur related to persistent submacular fluid and may be a cause of poor visual outcome.
Adolescent
;
Adult
;
Aged
;
Aged, 80 and over
;
Aqueous Humor/*metabolism
;
Child
;
Female
;
Follow-Up Studies
;
Humans
;
Male
;
Middle Aged
;
Photoreceptor Cells/*pathology
;
*Postoperative Complications
;
Prospective Studies
;
Retinal Detachment/*surgery
;
*Scleral Buckling
;
Tomography, Optical Coherence
;
Visual Acuity/physiology
;
Young Adult