Evisceration of Mouse Vitreous and Retina for Proteomic Analyses

While the mouse retina has emerged as an important genetic model for inherited retinal disease, the mouse vitreous remains to be explored. The vitreous is a highly aqueous extracellular matrix overlying the retina where intraocular as well as extraocular proteins accumulate during disease.^1-3 Abnormal interactions between vitreous and retina underlie several diseases such as retinal detachment, proliferative diabetic retinopathy, uveitis, and proliferative vitreoretinopathy.^1,4 The relative mouse vitreous volume is significantly smaller than the human vitreous (Figure 1), since the mouse lens occupies nearly 75% of its eye.⁵ This has made biochemical studies of mouse vitreous challenging. In this video article, we present a technique to dissect and isolate the mouse vitreous from the retina, which will allow use of transgenic mouse models to more clearly define the role of this extracellular matrix in the development of vitreoretinal diseases.     

Systems pathology analysis identifies neurodegenerative nature of age‐related vitreoretinal interface diseases

Aging is a phenomenon that is associated with profound medical implications. Idiopathic epiretinal membrane (iEMR) and macular hole (MH) are the major vision‐threatening vitreoretinal diseases affecting millions of aging people globally, making these conditions an important public health issue. iERM is characterized by fibrous tissue developing on the surface of the macula, which leads to biomechanical and biochemical macular damage. MH is a small breakage in the macula and is associated with many ocular conditions. Although several individual factors and pathways are suggested, a systems pathology level understanding of the molecular mechanisms underlying these disorders is lacking. Therefore, we performed mass spectrometry‐based label‐free quantitative proteomics analysis of the vitreous proteomes from patients with iERM and MH to identify the key proteins, as well as the multiple interconnected biochemical pathways, contributing to the development of these diseases. We identified a total of 1,014 unique proteins, many of which are linked to inflammation and the complement cascade, revealing the inflammation processes in retinal diseases. Additionally, we detected a profound difference in the proteomes of iEMR and MH compared to those of diabetic retinopathy with macular edema and rhegmatogenous retinal detachment. A large number of neuronal proteins were present at higher levels in the iERM and MH vitreous, including neuronal adhesion molecules, nervous system development proteins, and signaling molecules, pointing toward the important role of neurodegenerative component in the pathogenesis of age‐related vitreoretinal diseases. Despite them having marked similarities, several unique vitreous proteins were identified in both iERM and MH, from which candidate targets for new diagnostic and therapeutic approaches can be provided.     

Proteomic Interactions in the Mouse Vitreous-Retina Complex

Purpose

Human vitreoretinal diseases are due to presumed abnormal mechanical interactions between the vitreous and retina, and translational models are limited. This study determined whether nonstructural proteins and potential retinal biomarkers were expressed by the normal mouse vitreous and retina.

Methods

Vitreous and retina samples from mice were collected by evisceration and analyzed by liquid chromatography-tandem mass spectrometry. Identified proteins were further analyzed for differential expression and functional interactions using bioinformatic software.

Results

We identified 1,680 unique proteins in the retina and 675 unique proteins in the vitreous. Unbiased clustering identified protein pathways that distinguish retina from vitreous including oxidative phosphorylation and neurofilament cytoskeletal remodeling, whereas the vitreous expressed oxidative stress and innate immunology pathways. Some intracellular protein pathways were found in both retina and vitreous, such as glycolysis and gluconeogenesis and neuronal signaling, suggesting proteins might be shuttled between the retina and vitreous. We also identified human disease biomarkers represented in the mouse vitreous and retina, including carbonic anhydrase-2 and 3, crystallins, macrophage inhibitory factor, glutathione peroxidase, peroxiredoxins, S100 precursors, and von Willebrand factor.

Conclusions

Our analysis suggests the vitreous expresses nonstructural proteins that functionally interact with the retina to manage oxidative stress, immune reactions, and intracellular proteins may be exchanged between the retina and vitreous. This novel proteomic dataset can be used for investigating human vitreoretinopathies in mouse models. Validation of vitreoretinal biomarkers for human ocular diseases will provide a critical tool for diagnostics and an avenue for therapeutics.     

Proteomic Insight into the Molecular Function of the Vitreous

The human vitreous contains primarily water, but also contains proteins which have yet to be fully characterized. To gain insight into the four vitreous substructures and their potential functions, we isolated and analyzed the vitreous protein profiles of three non-diseased human eyes. The four analyzed substructures were the anterior hyaloid, the vitreous cortex, the vitreous core, and the vitreous base. Proteins were separated by multidimensional liquid chromatography and identified by tandem mass spectrometry. Bioinformatics tools then extracted the expression profiles, signaling pathways, and interactomes unique to each tissue. From each substructure, a mean of 2,062 unique proteins were identified, with many being differentially expressed in a specific substructure: 278 proteins were unique to the anterior hyaloid, 322 to the vitreous cortex, 128 to the vitreous base, and 136 to the vitreous core. When the identified proteins were organized according to relevant functional pathways and networks, key patterns appeared. The blood coagulation pathway and extracellular matrix turnover networks were highly represented. Oxidative stress regulation and energy metabolism proteins were distributed throughout the vitreous. Immune functions were represented by high levels of immunoglobulin, the complement pathway, damage-associated molecular patterns (DAMPs), and evolutionarily conserved antimicrobial proteins. The majority of vitreous proteins detected were intracellular proteins, some of which originate from the retina, including rhodopsin (RHO), phosphodiesterase 6 (PDE6), and glial fibrillary acidic protein (GFAP). This comprehensive analysis uncovers a picture of the vitreous as a biologically active tissue, where proteins localize to distinct substructures to protect the intraocular tissues from infection, oxidative stress, and energy disequilibrium. It also reveals the retina as a potential source of inflammatory mediators. The vitreous proteome catalogues the dynamic interactions between the vitreous and surrounding tissues. It therefore could be an indirect and effective method for surveying vitreoretinal disease for specific biomarkers.     

Comprehensive Analysis of Inflammatory Immune Mediators in Vitreoretinal Diseases

Inflammation affects the formation and the progression of various vitreoretinal diseases. We performed a comprehensive analysis of inflammatory immune mediators in the vitreous fluids from total of 345 patients with diabetic macular edema (DME, n = 92), proliferative diabetic retinopathy (PDR, n = 147), branch retinal vein occlusion (BRVO, n = 30), central retinal vein occlusion (CRVO, n = 13) and rhegmatogenous retinal detachment (RRD, n = 63). As a control, we selected a total of 83 patients with either idiopathic macular hole (MH) or idiopathic epiretinal membrane (ERM) that were free of major pathogenic intraocular changes, such as ischemic retina and proliferative membranes. The concentrations of 20 soluble factors (nine cytokines, six chemokines, and five growth factors) were measured simultaneously by multiplex bead analysis system. Out of 20 soluble factors, three factors: interleukin-6 (IL-6), interleukin-8 (IL-8), and monocyte chemoattractant protein-1 (MCP-1) were significantly elevated in all groups of vitreoretinal diseases (DME, PDR, BRVO, CRVO, and RRD) compared with control group. According to the correlation analysis in the individual patient''s level, these three factors that were simultaneously increased, did not show any independent upregulation in all the examined diseases. Vascular endothelial growth factor (VEGF) was significantly elevated in patients with PDR and CRVO. In PDR patients, the elevation of VEGF was significantly correlated with the three factors: IL-6, IL-8, and MCP-1, while no significant correlation was observed in CRVO patients. In conclusion, multiplex bead system enabled a comprehensive soluble factor analysis in vitreous fluid derived from variety of patients. Major three factors: IL-6, IL-8, and MCP-1 were strongly correlated with each other indicating a common pathway involved in inflammation process in vitreoretinal diseases.     

TGF-β-stimulated aberrant expression of class III β-tubulin via the ERK signaling pathway in cultured retinal pigment epithelial cells

The class III β-tubulin isotype (β_III) is expressed exclusively by neurons within the normal human retina and is not present in normal retinal pigment epithelial (RPE) cells in situ or in the early phase of primary cultures. However, aberrant expression of class III β-tubulin has been observed in passaged RPE cells and RPE cells with dedifferentiated morphology in pathologic epiretinal membranes from idiopathic macular pucker, proliferative vitreoretinopathy (PVR) and proliferative diabetic retinopathy (PDR). Transforming growth factor-β (TGF-β) has been implicated in dedifferentiation of RPE cells and has a critical role in the development of proliferative vitreoretinal diseases. Here, we investigated the potential effects of TGF-β on the aberrant expression of class III β-tubulin and the intracellular signaling pathway mediating these changes. TGF-β-induced aberrant expression and O-linked-β-N-acetylglucosamine (O-GlcNac) modification of class III β-tubulin in cultured RPE cells as determined using Western blotting, RT-PCR and immunocytochemistry. TGF-β also stimulated phosphorylation of ERK. TGF-β-induced aberrant expression of class III β-tubulin was significantly reduced by pretreatment with U0126, an inhibitor of ERK phosphorylation. Our findings indicate that TGF-β stimulated aberrant expression of class III β-tubulin via activation of the ERK signaling pathway. These data demonstrate that mature RPE cells have the capacity to express a neuron-associated gene in response to TGF-β stimulation and provide useful information towards understanding the pathogenesis of proliferative vitreoretinal diseases.     

Catalogue of soluble proteins in the human vitreous humor: comparison between diabetic retinopathy and macular hole

Two-dimensional gel electrophoresis and mass spectrometry were used to make a catalogue of soluble proteins in the human vitreous humor (VH). Fifty-one different proteins were identified on silver-stained two-dimensional (2D) gel patterns with VH proteins obtained from diabetic retinopathy and macular hole. Thirty of these have not been listed in the reported 2D profiles of plasma. Immunoglobulin (Ig), alpha1-antitrypsin, alpha2-HS glycoprotein,and complement C(4) fragment showed stronger spots in VH with diabetic retinopathy patient samples than those with macular hole. Pigment epithelium-derived factor, a potent inhibitor of angiogenesis in the cornea and vitreous, was clearly detected in VH with diabetes. It is impressive that the inhibitor increases in the vitreous with proliferative angiogenesis.     

Laser‐induced plasmon‐mediated treatment of retinoblastoma in viscous vitreous phantom

Retinoblastoma (RB) is a rare form of cancer of the retina most prevalent in young children. We successfully show that laser‐induced cell disruption, mediated by gold plasmonic nanoparticle (NP), is a potential and efficient therapy to kill the cancerous cells. The proof of concept is demonstrated in vitro on cultured Y79 RB cancer cells with a nanosecond laser at 527 nm, for both attached cells at the bottom of a Petri dish and for floating, clustered cells in a viscous vitreous phantom comprised of hyaluronan. We report a cellular death of 82% after irradiation in classic culture medium and a cellular death of 98% in vitreous phantom, for similar number of NPs in each sample. It is found that the NPs efficiently penetrate the floating Y79 clusters cells in the vitreous phantom, leading to a cellular death of over 85% even within the centre of the aggregates. The proposed treatment technique is based on a similar nanosecond laser used to eliminate floaters in the vitreous, but with much lower (100‐1000 times) fluences of 20 J cm^?2.      

玻璃体视网膜手术治疗先天性视网膜劈裂及其并发症的临床疗效

目的:评价玻璃体视网膜手术治疗先天性视网膜劈裂及其并发症的临床疗效。方法:选择2009年1月-2012年1月于我院进行玻璃体视网膜手术的先天性视网膜劈裂患者30例(42只眼),患者均接受了闭合式睫状体经扁平部三切口入路保留晶状体的玻璃体切割手术,并分析其术前及术后情况。结果:先天性视网膜劈裂患者中发生孔源性视网膜脱离19眼,牵拉性视网膜脱离8眼,玻璃体积血10眼,同时伴有视网膜脱离和玻璃体积血有5眼;在末次随访时视力提高者有36只眼,占85.71%,无提高者有6只眼,占14.29%;术前平均视力为(0.15±0.09),末次随访时平均视力提高至(0.31±0.16),两者平均视力差异具有统计学意义(t=5.649,P0.001);42只眼视网膜解剖结构复位良好,视网膜平伏;OCT检查结果显示,末次随访时黄斑劈裂平均面积(0.22±0.18)mm2,与术前黄斑劈裂平均面积(1.07±0.52)mm2比较,差异有统计学意义(t=10.011,P0.001),黄斑微囊样改变有改善;随访期间5只眼出现并发症,占11.90%,其中2眼术后发生PVR且伴牵拉性视网膜脱离,2只眼发生白内障,1只眼出现玻璃体积血,术后视网膜解剖均复位良好。结论:玻璃体视网膜手术可以帮助患者进行视网膜解剖复位及提高其先天性视网膜劈裂患者视功能,具有良好的临床疗效。     

Enhanced Vitreous Imaging in Healthy Eyes Using Swept Source Optical Coherence Tomography

Purpose

To describe enhanced vitreous imaging for visualization of anatomic features and microstructures within the posterior vitreous and vitreoretinal interface in healthy eyes using swept-source optical coherence tomography (SS-OCT). The study hypothesis was that long-wavelength, high-speed, volumetric SS-OCT with software registration motion correction and vitreous window display or high-dynamic-range (HDR) display improves detection sensitivity of posterior vitreous and vitreoretinal features compared to standard OCT logarithmic scale display.

Design

Observational prospective cross-sectional study.

Methods

Multiple wide-field three-dimensional SS-OCT scans (500×500A-scans over 12×12 mm²) were obtained using a prototype instrument in 22 eyes of 22 healthy volunteers. A registration motion-correction algorithm was applied to compensate motion and generate a single volumetric dataset. Each volumetric dataset was displayed in three forms: (1) standard logarithmic scale display, enhanced vitreous imaging using (2) vitreous window display and (3) HDR display. Each dataset was reviewed independently by three readers to identify features of the posterior vitreous and vitreoretinal interface. Detection sensitivities for these features were measured for each display method.

Results

Features observed included the bursa premacularis (BPM), area of Martegiani, Cloquet''s/BPM septum, Bergmeister papilla, posterior cortical vitreous (hyaloid) detachment, papillomacular hyaloid detachment, hyaloid attachment to retinal vessel(s), and granular opacities within vitreous cortex, Cloquet''s canal, and BPM. The detection sensitivity for these features was 75.0% (95%CI: 67.8%–81.1%) using standard logarithmic scale display, 80.6% (95%CI: 73.8%–86.0%) using HDR display, and 91.9% (95%CI: 86.6%–95.2%) using vitreous window display.

Conclusions

SS-OCT provides non-invasive, volumetric and measurable in vivo visualization of the anatomic microstructural features of the posterior vitreous and vitreoretinal interface. The vitreous window display provides the highest sensitivity for posterior vitreous and vitreoretinal interface analysis when compared to HDR and standard OCT logarithmic scale display. Enhanced vitreous imaging with SS-OCT may help assess the natural history and treatment response in vitreoretinal interface diseases.     

Composition, synthesis, and assembly of the embryonic chick retinal basal lamina

To study the biology of basal laminae in the developing nervous system the protein composition of the embryonic retinal basal lamina was investigated, the site of synthesis of its proteins in the eye was determined, and basal lamina assembly was studied in vivo in two assay systems. Laminin, nidogen, agrin, collagen IV, and XVIII are major constituents of the retinal basal lamina. However, only agrin is synthesized by the retina, whereas the other matrix constituents originate from cells of the ciliary body, the lens, or the optic disc. The synthesis from extraretinal tissues infers that the retinal basal lamina proteins must be shed from their tissues of origin into the vitreous body and from there bind to receptor proteins provided by the retinal neuroepithelium. The fact that all proteins typical for the retinal basal lamina are abundant in the vitreous body and a new basal lamina is only formed when the vitreous body was directly adjacent to the retina is consistent with the contention of the vitreous body having a function in retinal basal lamina formation. Basal lamina assembly was also studied after disrupting the retinal basal lamina by intraocular injection of collagenase. The basal lamina regenerated after chasing the collagenase with Matrigel, which served as a collagenase inhibitor. The basal lamina was reconstituted within 6 h. However, the regenerated basal lamina was located deeper in the retina than normal by reconstituting along the retracted neuroepithelial endfeet demonstrating that these endfeet are the preferred site of basal lamina assembly.     

Mutations in KCNJ13 cause autosomal-dominant snowflake vitreoretinal degeneration

Snowflake vitreoretinal degeneration (SVD, MIM 193230) is a developmental and progressive hereditary eye disorder that affects multiple tissues within the eye. Diagnostic features of SVD include fibrillar degeneration of the vitreous humor, early-onset cataract, minute crystalline deposits in the neurosensory retina, and retinal detachment. A genome-wide scan previously localized the genetic locus for SVD to a 20 Mb region flanked by D2S2158 and D2S2202. This region contains 59 genes, of which 20 were sequenced, disclosing a heterozygous mutation (484C > T, R162W) in KCNJ13, member 13 of subfamily J of the potassium inwardly rectifying channel family in all affected individuals. The mutation in KCNJ13, the gene encoding Kir7.1, was not present in unaffected family members and 210 control individuals. Kir7.1 localized to human retina and retinal pigment epithelium and was especially prevalent in the internal limiting membrane adjacent to the vitreous body. Molecular modeling of this mutation predicted disruption of the structure of the potassium channel in the closed state located immediately adjacent to the cell-membrane inner boundary. Functionally, unlike wild-type Kir7.1 whose overexpression in CHO-K1 cells line produces highly selective potassium current, overexpression of R162W mutant Kir7.1 produces a nonselective cation current that depolarizes transfected cells and increases their fragility. These results indicate that the KCNJ13 R162W mutation can cause SVD and further show that vitreoretinal degeneration can arise through mutations in genes whose products are not structural components of the vitreous.     

Assessment of Macular Function during Vitrectomy: New Approach Using Intraoperative Focal Macular Electroretinograms

Purpose

To describe a new technique to record focal macular electroretinograms (FMERGs) during vitrectomy to assess macular function.

Methods

Intraoperative FMERGs (iFMERGs) were recorded in ten patients (10 eyes) who undergo vitrectomy. iFMERGs were elicited by focal macular stimulation. The stimulus light was directed to the macular area through a 25 gauge (25G) glass fiber optic bundle. Background light was delivered through a dual chandelier-type light fiber probe. Focal macular responses elicited with combinations of stimulus and background luminances were analyzed.

Results

A stimulus luminance that was approximately 1.75 log units brighter than the background light was able to elicit focal macular responses that were not contaminated by stray light responses. Thus, a stimulus luminance of 160 cd/m² delivered on a background of 3 cd/m² elicited iFMEGs from only the stimulated area. This combination of stimulus and background luminances did not elicit a response when the stimulus was projected onto the optic nerve head. The iFMERGs elicited by a 10° stimulus with a duration of 100 ms and an interstimulus interval of 150 ms consisted of an a-, b-, and d-waves, the oscillatory potentials, and the photopic negative response (PhNR).

Conclusions

Focal ERGs with all components can be recorded from the macula and other retinal areas during vitreous surgery. This new technique will allow surgeons to assess the function of focal areas of the retina intraoperatively.     

The metabolism of naphthalene and its toxic effect on the eye

1. Naphthalene (1g./kg.) was fed daily by stomach tube to rabbits. 2. In more than half of the rabbits opacities in the lens and degeneration of the retina were visible in vivo. 3. Dissection of eye tissues revealed some or all of the following changes: a browning of the lens and eye humours, blue fluorescence of the eye humours and crystals in the retina and vitreous body. 4. The ascorbic acid concentration of the eye humours was decreased. 5. Some metabolites of naphthalene [1,2-dihydro-1,2-dihydroxynaphthalene, 2-hydroxy-1-naphthyl sulphate and (1,2-dihydro-2-hydroxy-1-naphthyl glucosid)uronic acid] are converted enzymically by the tissues of the eye into 1,2-dihydroxynaphthalene. 6. Changes in the eye are consistent with 1,2-dihydroxynaphthalene's being the primary toxic agent. The properties and reactions of this substance are described. 7. 1,2-Dihydroxynaphthalene is readily autoxidizable in neutral solution to form the yellow 1,2-naphthaquinone and hydrogen peroxide. This oxidation is reversed by ascorbate. 8. Ascorbate is oxidized catalytically by 1,2-naphthaquinone. This may account for the disappearance of ascorbate from the aqueous and vitreous humours of the eye after naphthalene feeding. It may also account for the appearance of crystals of calcium oxalate in the eye. 9. The brown colour of the lens of the naphthalene-fed rabbit is due to presence of naphthaquinone–protein compounds.     

Type VII Collagen Expression in the Human Vitreoretinal Interface,Corpora Amylacea and Inner Retinal Layers

Type VII collagen, as a major component of anchoring fibrils found at basement membrane zones, is crucial in anchoring epithelial tissue layers to their underlying stroma. Recently, type VII collagen was discovered in the inner human retina by means of immunohistochemistry, while proteomic investigations demonstrated type VII collagen at the vitreoretinal interface of chicken. Because of its potential anchoring function at the vitreoretinal interface, we further assessed the presence of type VII collagen at this site. We evaluated the vitreoretinal interface of human donor eyes by means of immunohistochemistry, confocal microscopy, immunoelectron microscopy, and Western blotting. Firstly, type VII collagen was detected alongside vitreous fibers6 at the vitreoretinal interface. Because of its known anchoring function, it is likely that type VII collagen is involved in vitreoretinal attachment. Secondly, type VII collagen was found within cytoplasmic vesicles of inner retinal cells. These cells resided most frequently in the ganglion cell layer and inner plexiform layer. Thirdly, type VII collagen was found in astrocytic cytoplasmic inclusions, known as corpora amylacea. The intraretinal presence of type VII collagen was confirmed by Western blotting of homogenized retinal preparations. These data add to the understanding of vitreoretinal attachment, which is important for a better comprehension of common vitreoretinal attachment pathologies.     

Blocking gastrin and CCK-B autocrine loop affects cell proliferation and apoptosis in vitro

Since its initial discovery as Ca²⁺/calmodulin (CaM)-dependent serine/threonine protein phosphatase, calcineurin (CaN) has been extensively studied in many mammalian tissues. CaN has been shown to be involved in various biological and Ca²⁺-dependent signal transduction pathways. Over the last decade, our laboratory has been interested and has carried out numerous experiments on this specific protein phosphatase. While, a lot of research has been performed studying CaN’s involvement in ischemia, the immune system, and various mammalian tissues, not much is known about the potential role of CaN in various eye diseases. This review focuses on the studies that have been carried out in our laboratory on CaN, and specifically CaN’s involvement in the eye. We demonstrated that CaN is localized in various eye tissues (cornea, iris, ciliary body, vitreous body, retina, choroid, sclera, and optic nerve) and that both its protein expression and activity were observed in high amounts in the retina, optic nerve and cornea. Recently, we have cloned and characterized the CaN A and B subunits in the bovine retina. These initial findings suggest that CaN may play a potential role in visual transduction and various ocular diseases, including cancer.     

Update on current surgical management of idiopathic macular holes

Idiopathic macular holes were generally considered an untreatable condition until 1991 when the first papers reported successful closure of macular holes and visual improvement using pars plana vitrectomy, peeling of the cortical vitreous and face-down positioning. Since that time, the original pathogenesis theory has been refined as well as surgical methods and techniques. Currently, macular hole surgery is considered the most successful vitreoretinal surgery, with a greatly improved prognosis for patients. This article will review the general characteristics of macular holes and the clinical trials and outcomes that have led to the latest techniques in idiopathic macular hole surgery.     

玻璃体腔联合注射赖氨酸－纤溶酶原和瑞替普酶诱导兔眼玻璃体后脱离的有效性

目的:探讨兔眼玻璃体腔联合注射赖氨酸-纤溶酶原和瑞替普酶诱导玻璃体后脱离(PVD)的有效性。方法:选取30只健康的新西兰白兔,以白兔右眼作为实验眼,左眼作为对照眼。随机分为A、B、C三组(每组10只),三组实验眼分别联合应用1万U瑞替普酶+125μg赖氨酸—纤溶酶原、2万U瑞替普酶+125μg赖氨酸—纤溶酶原、3万U瑞替普酶+125μg赖氨酸—纤溶酶原进行玻璃体腔内注射,对照眼均注射平衡盐溶液。应用视网膜电图、扫描电镜及光镜观察、比较各组诱导PVD的效果。结果:三组实验眼均形成不同程度PVD。A组实验眼注药前与注药后24 h、注药后2周的最大混合反应a波振幅、b波振幅比较均无明显差异(P0.05);B组实验眼注药后24 h的a波振幅、b波振幅均有轻度下降,2周后均恢复正常,注药前后的a波振幅、b波振幅比较均无明显差异(P0.05)。C组实验眼注药后24 h的a波振幅、b波振幅均明显低于注药前和对照眼,注药后2周的b波振幅均明显低于注药前和对照眼(P0.05)。光学组织切片观察显示:A组实验眼及所有对照眼、B组实验眼、C组实验眼的视网膜组织细胞形态正常,结构清晰,但B组神经节内核层、细胞层细胞略有减少,C组神经节内核层及细胞层细胞明显减少。结论:玻璃体腔内联合注射赖氨酸-纤溶酶原和瑞替普酶能有效诱导PVD,1万U瑞替普酶+125μg赖氨酸-纤溶酶原可诱导实现完全性PVD,不会对视功能、视网膜结构造成损害。     

Substance P and secretoneurin in vitreous aspirates of patients with various vitreoretinal diseases

By means of highly sensitive radioimmunoassays, the levels of substance P (SP) and secretoneurin (SN) were detected in vitreous aspirates of patients with macular holes which served as controls, in patients with nonproliferative diabetic retinopathy (DR), active proliferative diabetic retinopathy (active PDR), inactive PDR, rhegmatogenous retinal detachment and proliferative vitreoretinopathy (PVR). Furthermore, SN-like immunoreactivities were characterized by reversed phase-HPLC. The concentration of SN was more than 20-fold higher in macular holes when compared with SP and reversed phase HPLC revealed evidence that the vitreous levels of SN represent authentic SN. SN was significantly decreased in patients with nonproliferative DR, active PDR and inactive PDR by more than 70% which seems to result from a reduced expression and/or secretion from the cilary epithelium and a reduced release from the retina both due to diabetes mellitus. By contrast SP was increased in rhegmatogenous retinal detachment most obviously due to an enhanced outflow of the peptide through retinal breaks. Despite their proangiogenic activities, SP and SN are unlikely to be involved in the pathogenesis of neovascularizations in DR because of their unchanged and reduced levels, respectively, but the low levels of both peptides may facilitate the regression of vasoproliferations following laser photocoagulation.