钠尿肽受体A在小鼠视网膜发育过程中的表达

目的检测钠尿肽受体(NPR)在不同年龄小鼠视网膜内的表达,探讨其在视网膜发育过程中的作用。方法收集从受孕16日(E16)到出生90日(P90)小鼠眼球标本共127只,对NPR-A进行免疫荧光检测。结果NPR-A广泛存在于视网膜神经元中,例如,在外核层,NPR-A于P7开始高表达在视锥、视杆细胞内、外突起上,于P14减弱,P30之后持续稳定弱表达;在内核层,从P7开始NPR-A持续弱表达在双极细胞的突起中,而在水平细胞中未见NPR-A表达;在神经节细胞层,NPR-A于E16开始高表达在神经节细胞胞体中,P14明显减弱,而在神经纤维层,即神经节细胞的轴突中,NPR-A从胚胎期至成年持续高表达;在外网状层和内网状层,NPR-A于P14均高表达,但于P30之后逐渐减弱。此外,NPR-A还广泛的存在于Müller细胞的突起中。结论 NPR-A参与了视网膜的发育,可能是小鼠视网膜神经元发育过程中的关键分子,并对Müller细胞的功能活动起着重要的调节作用。     

Expression profile of heat shock protein 108 during retinal development in the chick

In the developing chick retina, heat shock protein 108 (HSP108), which exhibits transferrin binding activity, has been demonstrated at the mRNA level, while transferrin shows two expression peaks. Here, we investigated the expression profile of HSP108 in the developing chick retina at the protein level. The localization of HSP108 in embryonic days 15 (E15), E18, and postnatal day 2 (P2) chick retina was examined immunohistochemically using monoclonal antibody 9G10 specific for chick HSP108, while the expression levels of HSP108 in developing chick retina from E12 to P2 and adult were measured by Western blot analysis. HSP108 was expressed in the ganglion cell layer, inner nuclear layer, outer plexiform layer, outer nuclear layer, inner segments of photoreceptors and retinal pigment epithelium. Two peaks of HSP108 expression were found at around E13 and E18, respectively. Since the two HSP108 peaks appeared to be correlated with the transferrin expression peaks during retinal development, HSP108 may be associated with iron metabolism during the development of the retina.     

Immunohistochemical localization of protein kinase C (PKC) beta I in the pig retina during postnatal development

In order to investigate the expression of protein kinase C (PKC) beta I in the retinas of pigs during postnatal development, we analyzed retinas sampled from 3-day-old and 6-month-old pigs by Western blotting and immunohistochemistry. Western blot analysis detected the expression of PKC beta I in the retinas of 3-day-old piglets and it was increased significantly in the retinas of 6-month-old adult pigs. Immunohistochemical staining showed PKC beta I in the retinas of both groups. Immunohistochemistry of 3-day-old retinas revealed weak PKC beta I reactivity in the ganglion cell layer, inner plexiform layer, inner nuclear cell layer, outer plexiform layer and rod and cone cell layer. In the 6-month-old pig retina, the cellular localization of PKC beta I immunostaining was similar to that of the 3-day-old retina, where PKC beta I was localized in some glial fibrillary acidic protein-positive cells, glutamine synthetase-positive cells, parvalbumin-positive cells, and PKC alpha-positive cells in the retina. This is the first study to show the expression and cellular localization of PKC beta I in the retina of pigs with development, and these results suggest that PKC beta I, in accordance with PKC alpha, plays important roles in signal transduction pathways in the pig retina with development.     

Immunohistochemical localization of protein kinase C-alpha in the retina of pigs during postnatal development

The cellular localization and protein expression level of protein kinase C (PKC)-alpha was examined in pig retina at different ages. Western blot analysis detected PKC-alpha in the retinas of 3-day-old piglets and indicated significantly increased expression in 6-month-old young adult and 2-year-old adult pigs. Immunohistochemistry of 3-day-old retinas revealed intense PKC-alpha reactivity in the inner plexiform and inner nuclear cell layers, weak reactivity in the ganglion cell layer, and few positive cells in the outer nuclear cell layer. The cellular localization of PKC-alpha in the adult retina was similar, with staining more intense than that in neonates. PKC-alpha was co-localized in some glial fibrillary acidic protein-positive cells and glutamine synthetase-positive cells in the retina. This study demonstrates that the protein level of retinal PKC-alpha is increased with maturation and suggests that PKC-alpha plays a role in signal transduction pathways for postnatal development in porcine retina.     

GABAc受体ρ1亚单位mRNA在大鼠视网膜和移植视网膜的定位

应用原位杂交组织化学技术及放射自显影技术 ,通过同位素 [35 S] -d ATP标记寡聚核苷酸探针 ,研究了 GABAc受体ρ1亚单位 m RNA在大鼠视网膜和移植视网膜的定位。实验结果发现 :ρ1亚单位 m RNA在大鼠视网膜和移植视网膜的分布相似 ,它们都分布在内核层中部和外侧部 (即近外网层侧 ) ,胞体呈椭圆形或卵圆形。正常大鼠视网膜 ρ1亚单位 m RNA杂交阳性细胞最先出现于生后第 12 d;移植视网膜出现于术后第 18d(即相当于正常视网膜生后第 10 d)。杂交阳性细胞的形态和位置提示 :表达 GABAc受体ρ1亚单位 m RNA的细胞可能是视网膜双极细胞。这为揭示视网膜信息调控提供了重要依据     

Neuronal expression of P2X3 purinoceptors in the rat retina

P2X3 purinoceptors are involved in fast, excitatory neurotransmission in the nervous system, and are expressed predominantly within sensory neurons. In this study, we examined the cellular and synaptic localization of the P2X3 receptor subunit in the retina of the rat using immunofluorescence immunohistochemistry and pre-embedding immunoelectron microscopy. In addition, we investigated the activity of ecto-ATPases in the inner retina using an enzyme cytochemical method. The P2X3 receptor subunit was expressed in the soma of a subset of GABA immunoreactive amacrine cells, some of which also expressed protein kinase C-alpha. In addition, punctate immunoreactivity was observed within both the inner and outer plexiform layers of the retina. Double labeling studies showed that P2X3 receptor puncta were associated with both rod and cone bipolar cell axon terminals in the inner plexiform layer. Ultrastructural studies indicated that P2X3 receptor subunits were expressed on putative A17 amacrine cells at sites of reciprocal synaptic input to the rod bipolar cell axon terminal. Moreover, we observed P2X3 immunolabeling on amacrine cell processes that were associated with cone bipolar cell axon terminals and other conventional synapses. In the outer retina, P2X3 immunoreactivity was observed on specialized junctions made by putative interplexiform cells. Ecto-ATPase activity was localized to the inner plexiform layer on the extracellular side of all plasma membranes, but was not apparent in the ganglion cell layer or the inner nuclear layer, suggesting that ATP dephosphorylation occurs exclusively in synaptic regions of the inner retina. These data provide further evidence that purines participate in retinal transmission, particularly within the rod pathway.     

Roller organ cultures of the retina from postnatal rats

Whole retinas of 2–14-day-old rats were cultured in a roller device for 2–14 days. Floating retinas of 7–14-day-old rats formed hole spheroid structures (spheroids) with the wall completely retaining the linear structure and layer-by-layer cellular and fibrous architecture, including the outer nuclear, outer plexiform, inner nuclear, inner plexiform layers, layers of ganglion cells and nerve fibers. The retina obtained at earlier terms of development often formed folds, with pyknotic nuclei of dead neurons in their deep compartments. In organ cultures of the retina isolated from rats at early postnatal periods, rosettes were formed in sites of local injury to the outer nuclear layer and pigmented epithelium. Roller organ cultures can be used for in vitro studies of the development and experimental diseases of the retina. __________ Translated from Byulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 142, No. 10, pp. 471–474, October, 2006     

Histological and electron microscopic milestones in the development of the retina of a marsupial wallaby, Macropus eugenii

Summary Retinal differentiation in the pouch young of the wallaby Macropus eugenii was characterized microscopically and morphometrically. Mitosis occurs until early in the second month in the central retina, and until early in the fourth month, peripherally. Separation of the neuroblast layer by the outer plexiform layer did not immediately halt cell division. The retinal surface continued to expand well past the time of cessation of proliferation. Cell death in the ganglion cell layer continued through the fourth month centrally and to nearly five months in the periphery. The major period of cell death was coincident with the segregation of retinal afferents and the refinement of topography in the superior colliculus and dorsal lateral geniculate necleus. Beginning in the third month retinal thickness, measured between the outer limiting membrane and nerve fiber layer declined equally in peripheral and central regions. At all stages the combined thicknesses of the outer and inner nuclear layer in the retinal periphery was greater than that in the center. Together with a late thickening of the inner plexiform layer, the data are consistent with the suggestion that expansion of peripheral non-ganglion cell elements may play a role in development of center to periphery differences in ganglion cell distributions.Retinal differentiation of the wallaby follows the pattern of most mammals. The onset of development of key milestones for the acquisition of retinal function occurred in the sequence: conventional synapse formation prior to ribbon synapse formation in the inner plexiform layer, and photoreceptor outer segment differentiation prior to terminal triad synapse formation.     

信号转导子与转录激活子3蛋白在金黄地鼠视网膜生后早期发育过程中的表达

目的 观察信号转导子与转录激活子3(STA13)蛋白在金黄地鼠视网膜生后早期发育过程中的表达。方法 STA13蛋白免疫细胞化学染色和Westem免疫印迹方法结果生后发育早期整个视网膜神经层均有STA13阳性产物分布,以视网膜节细胞层(GcL)、内网层(IPL)和成神经细胞层(NBL)的内层更明显,随着发育进程,其阳性产物逐渐局限于视网膜节细胞的胞浆和胞核;蛋白半定量结果显示,生后1周内STA13蛋白表达水平较高,之后逐渐降低,成年后最低。结论 STA13蛋白的表达及变化可能与视网膜生后早期发育密切相关。     

Spatial and temporal distribution patterns of enkephalinergic neurons in adult and developing retinas of the preproenkephalin-green fluorescent protein transgenic mouse

Enkephalin (ENK) peptides are present in the retina of several vertebrate species and play a crucial role in establishing specific circuits during retinal development. However, there is no information available concerning the development of ENKergic neurons in the mouse retina. To address this question, we used preproenkephalin-enhanced green fluorescent protein (GFP) transgenic mice, in which ENKergic neurons are revealed by GFP. Our results showed that most GFP-positive cells were located in the proximal part of the inner nuclear layer with a scattering of GFP-immunoreactive cells in the ganglion cell layer (GCL) in the adult retina. Double immunostaining with syntaxin indicates that GFP expression was restricted to a population of amacrine cells. The proportions of glycine transporter-1 and γ-aminobutyric acid-positive cells among ENKergic neurons were 57.3 ± 2.4% and 10.1 ± 1.8%, respectively. We then injected retrograde tracer into the superior colliculus and observed that none of the ENKergic neurons in the GCL were retrogradely labeled with the tracer. GFP-positive cells were first observed at embryonic day (E) 15 in the inner neuroblastic layer at only very low levels, which gradually increased until E18. After birth, there was a steep rise in GFP expression levels, reaching maximal activity by postnatal day (P) 7. The distribution and intensity of GFP-positive cells at P15 were similar to those of adult retina. It was found that immunoreactive processes in the inner plexiform layer formed strongly stained patches. The present results provide detailed morphological evidence of the cell type and spatial and temporal distribution of ENKergic neurons in the retina.     

Histology of the ferret retina

The retina of the adult ferret, Mustelo furo, was studied with light and transmission electron microscopy to provide an anatomical basis for use of the ferret as a model for retinal research. The pigment epithelium is a simple cuboidal layer of cells characterized by a zone of basal folds, apical microvilli, and pigment granules at various stages of maturation. The distinction between rod and cone photoreceptor cells is based on their location, morphology, heterochromatin pattern and the electron density of their inner segments. The round, light-staining cone cell nuclei occupy the layer of perikarya along the apical border of the outer nuclear layer. The remainder of the outer nuclear layer consists of oblong, deeply-stained rod cell nuclei. Ribbon type synaptic complexes involving photoreceptor cell axons, horizontal cell processes, and bipolar cell dendrites characterize the outer plexiform layer. The inner nuclear layer is comprised of horizontal, bipolar, and amacrine cell perikarya as well as the perikarya of the Müller cells. The light-staining horizontal cell nuclei are prominent along the apical border of the inner nuclear layer. The light-staining amacrine cell nuclei form a more or less continuous layer along the basal border of the inner nuclear layer. Both conventional and ribbon-type synapses characterize the inner plexiform layer. The ganglion cells form a single cell layer. The optic fiber layer contains bundles of axons surrounded by Müller cell processes. Small blood vessels and capillaries are present in the basal portion of the retina throughout the region extending from the internal limiting membrane to the outer plexiform layer. The adult one-year-old retina is compared with the retina at the time of eye opening.     

高血压大鼠视网膜溶酶体酶组织化学研究

目的：探讨溶酶体酶在高血压视网膜网变发生过程中的作用。方法：应用光镜定量酶组织化学方法对ＷＫＹ大鼠和自发性高血压大鼠视网膜原酸性磷酸的分布和活性变化进行定量观察。结果：视网膜各层酸性磷酸酶活性岂强到弱依次是（Ｆ检验，Ｐ〈０．０５）；（１）色素上皮层；（２）视杆维层内节和外网层（两层间活性无显著性差异）；（３）内网层；（４）节细胞层和神经纤维层，（５）外核层和内核层（两层间活性无显著性差异）杆锥层外     

游离锌离子在小鼠视网膜的定位研究

目的研究游离锌离子在小鼠视网膜的定位分布。方法应用ZnSe金属自显影技术(AMG)检测硒酸钠注射40 m in后小鼠视网膜内的锌离子。结果注射硒酸钠40 m in后发现游离锌离子主要分布于小鼠视网膜的色素上皮细胞层、光感受器的内节、外核层、外网层、内核层、内网层和神经节细胞层。在色素上皮细胞层、光感受器的内节和内核层与内网层交界处AMG阳性反应最为明显,在光感受器外节和神经纤维层几乎没有AMG阳性反应产物。结论小鼠视网膜内锌离子,在视网膜神经元视觉信息的传导和形成过程中可能起着重要作用。     

Generation of retinal cells in the wallaby, Setonix brachyurus (quokka)

We have examined the generation of retinal cells in the wallaby, Setonix brachyurus (quokka). Animals received a single injection of tritiated thymidine between postnatal days 1-85 and retinae were examined at postnatal day 100. Retinae were sectioned, processed for autoradiography and stained with Cresyl Violet. Ganglion cells were labelled by injection of horseradish peroxidase into the optic tracts and primary visual centres. Other cells were classified according to their morphology and location. Retinal cell generation takes place in two phases. During the first phase, which concludes by postnatal day 30, cells destined to lie in all three cellular layers of the retina are produced. In the second phase, which starts by postnatal day 50, cell generation is almost entirely restricted to the inner and outer nuclear layers. Cells produced in the first phase are orthotopic and displaced ganglion cells, displaced and orthotopic amacrine cells, horizontal cells and cones. Glia in the ganglion cell layer, orthotopic amacrine cells, bipolar and horizontal cells. Muller glia, and rods are generated in the second phase. Cells became heavily labelled with tritiated thymidine in the central retina before postnatal day 7, over the entire retina (panretinal) by postnatal day 7 and from postnatal day 18, only in the periphery. The second phase of cell generation is initiated at P50, in a region extending from the optic nerve head to mid-temporal retina. Subsequently, cells are generated in annuli, centred on mid-temporal retina, which are seen at progressively more peripheral locations. Therefore, cell addition to the inner and outer nuclear layers continues for longer in peripheral than in mid-temporal retina. We suggest that such later differential cell addition to the inner and outer nuclear layers contributes to an asymmetric increase in retinal area. This non-uniform growth presumably results in more expansion of the ganglion cell layer peripherally than in mid-temporal retina and may play a role in establishing density gradients of ganglion cells.     

Tyrosine hydroxylase immunoreactive interplexiform cells in the lamprey retina

The distribution of tyrosine hydroxylase immunoreactivity was investigated in retinae of metamorphic, postmetamorphic and adult lampreys. Immunoreactive cell bodies were located mainly in the innermost part of the inner nuclear layer, with a few cells scattered throughout the inner plexiform layer. The processes of these neurons ran preferentially in the inner plexiform layer. Additionally, dense plexus of labelled processes were observed in the outer plexiform and nuclear layers. These findings suggest that most of the tyrosine hydroxylase-immunoreactive cells in the lamprey retina are interplexiform cells.     

Expression of Glutamate and GABA during the Process of Rat Retinal Synaptic Plasticity Induced by Acute High Intraocular Pressure

Acute high intraocular pressure (HIOP) can induce plastic changes of retinal synapses during which the expression of the presynaptic marker synaptophysin (SYN) has a distinct spatiotemporal pattern from the inner plexiform layer to the outer plexiform layer. We identified the types of neurotransmitters in the retina that participated in this process and determined the response of these neurotransmitters to HIOP induction. The model of acute HIOP was established by injecting normal saline into the anterior chamber of the rat eye. We found that the number of glutamate-positive cells increased successively from the inner part to the outer part of the retina (from the ganglion cell layer to the inner nuclear layer to the outer nuclear layer) after HIOP, which was similar to the spatiotemporal pattern of SYN expression (internally to externally) following HIOP. However, the distribution and intensity of GABA immunoreactivity in the retina did not change significantly at different survival time post injury and had no direct correlation with SYN expression. Our results suggested that the excitatory neurotransmitter glutamate might participate in the plastic process of retinal synapses following acute HIOP, but no evidence was found for the role of the inhibitory neurotransmitter GABA.     

高血压大鼠视网膜组织Ca^2＋酸性磷酸酶组织化学的研究

目的：应用光镜定量酶组织化学方法对正常京都种大鼠（ＷＫＹ）和自发性高血压大鼠（ＳＨＲ）视网膜组织的Ｃａ＾２＋－酸性磷酸酶的分布和活性进行定量观察，结果：Ｃａ＾２＋酸性磷酸酶在ＷＫＹ视网膜组织的活性由强到弱依次为（Ｆ检验，Ｐ〈０．０５）；（１）杆锥细胞内节和外核层；（２）节细胞层；（３）内核层；（４）内网层和外网层；（５）杆锥细胞外节阴性，在ＳＨＲ视网膜组织中，各层Ｃａｓ＾２＋酸性磷酸酶活性下降，以