大鼠,金黄地鼠和家兔视网膜内一氧化氮合酶分布的比较

用ＮＡＤＰＨ黄递酶组织化学染色法观察了正常成年大鼠、金黄地鼠和家兔视网膜内一氧化氮合酶的分布，并比较了３种不同动物的区别。结果显示，在视网膜内ＮＯＳ阳性神经元主要为分布于内核层的无长突细胞、节细胞层的移位无长突细胞和少数节细胞，不同种类动物的视网膜内，ＮＯＳ阳性细胞的配布、密度和细胞形态均有差异。大鼠视网膜内ＮＯＳ阳性细胞多尾于内核层无长突细胞和节细胞层移位无长细胞，偶见于视网膜节细胞。金黄地鼠视     

Demonstration of a substance P-like immunoreactivity in retinal cells of the rat

The distribution of substance P (SP)-like immunoreactivity in the rat retina was investigated by immunohistochemistry. SP-positive cells were found throughout the retina. The majority of them were located in the proximal portion of the inner nuclear layer and the processes from these cells directed to the inner plexiform layer where they ramified, suggesting that SP-positive cells located in this region probably are amacrine cells. Few SP-positive cells were seen within the ganglion cell layer. They were considered displaced amacrine cells.     

Immunohistochemical evidence for epinephrine-containing retinal amacrine cells

The enzyme for the synthesis of epinephrine, phenylethanolamine-N-methyltransferase, has been localized, by an indirect immunofluorescent staining method, to a subpopulation of amacrine cells in the rat retina. The immunoreactive cells are located primarily in the inner nuclear layer and send a single process to the inner plexiform layer. Most of the immunoreactivity is found in the center of the inner plexiform layer. A small percentage of immunoreactive cell bodies were found in the inner plexiform layer and occasionally cells were observed in the ganglion cell layer. These epinephrine-containing amacrine cells are morphologically distinct from the dopamine-containing amacrine cells previously described by formaldehyde fluorescence and we speculate from reports in the literature that epinephrine-containing amacrine cells may play a role in modulating the activity of dopamine-containing amacrine cells.     

自发性高血压大鼠视网膜内含一氧化氮合酶神经元的研究

本实验用ＮＡＤＰＨ－黄递酶组织化学染色法观察了自发性高血压大鼠和京都种大鼠（ＷＫＹ，正常对照）视网膜内一氧化氮合酶（ＮＯＳ）的变化。结果显示，ＮＯＳ阳性神经元位于内核层和视网膜节细胞层。ＳＨＲ组视网膜ＮＯＳ阳性细胞属无长突细胞和移位无长突细胞。偶见最怀的节细胞。ＮＯＳ阳性无长突细胞和节细胞胸质显强阳性反应，可较长而清晰的突起，ＮＯＳ阳性神经元的分布密度长，且在视网膜中央区（视神经盘附近）的分布密度     

Neuronal and glial localization of homocysteate-like immunoreactivity in the rat retina

Summary To study the distribution ofl-homocysteate in the rat retina, specific polyclonal and monoclonal anti-homocysteate antibodies have been used in combination with a highly sensitive postembedding method for light microscopic immunocytochemistry. In central and peripheral retina, the most strongly immunoreactive cell bodies lay in the inner nuclear layer. They represented about 17% of the total neuronal cell population of the layer and were identified as bipolar cells (19–20% of cells in the outer half of the inner nuclear layer) and amacrine cells (15% of cells in the inner half of the inner nuclear layer). A third cell type showing heavy homocysteate-like immunoreactivity was identified as Müller glial cells. Characteristically, their descending processes formed three immunoreactive bands in the inner plexiform layer. Furthermore, the outer and inner limiting membranes as well as glia around and between ganglion cell axons and in the vicinity of blood vessels were labelled intensely. Photoreceptors and their terminals, and ganglion cells, were not immunostained. These findings indicate the presence of homocysteate in some bipolar and amacrine cells of the inner nuclear layer and support a role for this sulphur-containing excitatory amino acid as a neurotransmitter candidate in the retina.     

Distribution and ontogeny of parvalbumin immunoreactivity in the chicken retina.

The distribution of parvalbumin-like immunoreactivity was studied in the embryonic and postnatal chicken retina. In post-hatched chickens, parvalbumin-like immunoreactivity was confined to amacrine cells. Three distinct subpopulations were identifiable based upon soma position and level of dendritic arborization in the inner plexiform layer. The primary dendrites from parvalbumin-immunoreactive amacrine cells descended vertically into the inner plexiform layer and eventually branched to give rise to a laminarly arrayed plexus in sublamina I, sublamina V and, to a lesser extent, at the boundary between sublaminae III and IV. Parvalbumin-like immunoreactive amacrine cells projecting to sublamina I of the inner plexiform layer were consistently monostratified. Some, but not all, contributed thick fibers to sublamina I that could be followed for long distances across the retina and were generally not radially organized. The parvalbumin-like immunoreactive cells that projected to sublamina V gave rise to a primary dendrite from which three to five fibers branched radially. Collateral branches of these same primary dendrites gave rise to the parvalbumin-like immunoreactive plexus at the interface between sublaminae III and IV. In prenatal chickens, parvalbumin-like immunoreactivity was not detected until embryonic day 14. At this time it appeared as a faint band at the inner nuclear layer-inner plexiform layer boundary in the central retina. By embryonic day 18 the intensity of immunoreactivity and the complexity of the arborizations of the parvalbumin-like immunoreactive dendrites approached that seen in the post-hatched chicken. In the chicken retina, parvalbumin-like immunoreactivity was displayed by morphologically distinct subpopulations of amacrine cells suggesting that these amacrine cells may subserve diverse functions.(ABSTRACT TRUNCATED AT 250 WORDS)     

The immunocytochemical localization of neuronal nitric oxide synthase in the developing rat retina

The localization of nitric oxide synthase (NOS) was investigated in the developing rat retina by immunocytochemistry and western blot analysis, using an antiserum directed against neuronal NOS. NOS-labeled cells were first detected at postnatal day 5 (P5) in the inner row of the neuroblastic layer. These cells were considered to correspond to the type 1 cell of the adult rat retina. Type 2 cells, characterized by a small soma and weak immunoreactivity, and a class of displaced amacrine cells were detected at P9 and P7, respectively. By P14 or P15, the time of eye opening, NOS immunoreactivity appeared in some bipolar cells. NOS was first expressed at the protein level at P9. Thereafter, quantitative evaluation by immunoblotting confirmed that the intensity of the immunoreactive bands increased abruptly, reaching the same value as is found in the adult retina at P21. Our results demonstrate that differentiation of NOS-labeled cells follows a discrete developmental pattern and is most active during the 2nd postnatal period in the rat retina.     

Nitric oxide synthase expression in the transient ischemic rat retina: neuroprotection of betaxolol

Betaxolol is a β-adrenergic blocker but its neuroprotective action is generally thought to be due to its calcium channel blocking properties. In this study, we investigated neuronal cell damage and changes in the expression of neuronal nitric oxide synthase (nNOS) immunoreactivity in the ischemic retina and its relationship to the neuroprotection of betaxolol treatment after ischemic injury. Using the retina after ischemia, the expression of nNOS was studied by immunocytochemistry. In control retinas, two types of amacrine cells and a class of displaced amacrine cells were nNOS-labeled. After ischemia/reperfusion, the number of nNOS immunoreactive cells increased in both the ganglion cell layer and the inner nuclear layer compared to the control retinas. However, when experiments were carried out on animals that had been treated with betaxolol twice daily after ischemia/reperfusion, the number of nNOS immunoreactive cells decreased compared to the untreated ischemic retinas. These results suggest that an increase in nNOS expression could be associated with the degenerative changes in the ischemic retina, and that betaxolol treatment appears to play a role in protecting retinal tissue from ischemic damage.     

Discrete distributions of putative cholinergic and somatostatinergic amacrine cell dendrites in chicken retina

The distributions of putative cholinergic and somatostatinergic amacrine cells of the chicken retina were compared. Acetylcholinesterase-positive amacrine cell bodies were concentrated at the border between the inner nuclear and plexiform layers. Similar amacrine cell bodies were detected in a displaced position in the ganglion cell layer. Both populations had dendrites joining the 4 bands of acetylcholinesterase activity in the inner plexiform layer. The cell bodies of somatostatin-immunoreactive amacrine cells were distinct from the intensely acetylcholinesterase-positive cell bodies. The immunoreactive terminal bands did not overlap the acetylcholinesterase-positive bands, except in the inner parts of the inner plexiform layer.     

大鼠视网膜神经元NOS与Parvalbumin的共存研究

用NADPH脱氢酶组化及Parvalbumin免疫组化双标记技术观察了正常大鼠视网膜一氧化氮合酶(NOS)与Parvalbumin(PV)的分布,结果显示NOS阳性神经元主要位于内核层内缘带第二列,少数位于节细胞层,胞体圆形/卵圆形,直径8～12μm,细胞一侧发出突起伸向内网层1、3、5亚层,以第3亚层最为明显,PV免疫反应(PV—Ⅰ)神经元位于内核层最内缘第一列,少数位于第二列、中间部及节细胞层,胞体卵圆形,直径6～10μm,由胞体一端发出突起伸向内网层第1、5亚层.神经纤维层可见PV～Ⅰ纤维.内核层内缘第二列可见少数双标阳性细胞,在它们的PV免疫反应胞质内散布有NOS颗粒.实验结果表明 NOS阳性神经元与PV～Ⅰ神经元均为无长突细胞,分属不同的亚型,少效PV～Ⅰ神经元属节细胞,个别双标细胞可能为另一种亚型的无长突细胞,提示NOS与PV在视觉信息传递中可能存在某些联系.     

Localization of substance P-like immunoreactivity in the adult and developing goldfish retina

Substance P-like immunoreactivity was localized to amacrine cells in both adult and developing goldfish retina using immunohistochemical techniques. These studies utilized a well-characterized monoclonal antiserum directed to substance P. Specificity was established by absorption of the anti-serum with 10 μm synthetic substance P. Specific substance P-like immunoreactivity was localized within a seemingly distinct population of unistratified amacrine cells which were distributed in both central and peripheral retinal regions. The immunoreactive somata were located at the border of the inner nuclear layer and inner plexiform layer and were characterized by a round or ovoid somata which measured about 9μm in diameter. These immunoreactive amacrine cells typically had a single process which descended to and ramified within lamina 3 of the inner plexiform layer.Specific substance P-like immunoreactivity first appeared 60 h after hatching (stage 27) within both somata and processes located in differentiated retinal regions. No substance P-like immunoreactive somata or processes were observed in undifferentiated retinal regions. In retinas from stage 27 to 14 days after hatching, the immunoreactive somata were characterized by an ellipsoidal soma and a large nucleus devoid of immunoreactivity. These immunoreactive cells were also characterized by a single process that descended to and ramified within lamina 3 of the differentiated inner plexiform layer. At 30 days after hatching, the substance P-containing cells were identical in appearance to these same cell types observed within the adult retina.     

Immunohistochemical localization of heat shock protein 27 in the retina of pigs

The expression of heat shock protein 27 (HSP27) was examined in the retinas of pigs. Western blot analysis detected the expression of HSP27 in the retinas of 1-day-old piglets and showed that it was enhanced in the retinas of 6-month-old adult pigs. Immunohistochemically, HSP27 immunostaining was seen mainly in ganglion cell bodies in the ganglion cell layer, and in some processes of astrocytes in the innermost nerve fiber layer. In 1-day-old piglets, HSP27 was detected weakly in the inner plexiform, inner nuclear cell, outer plexiform, and rod and cone layers. The HSP27 immunoreactivity across the retinal layers was enhanced in the retinas of 6-month-old pigs compared with newborn piglets. The HSP27 immunoreactivity in the radial processes of Müller cells was particularly prominent in adult pig retinas. In summary, this finding suggests that HSP27 plays an important role in signal transduction of glial cells and neuronal cells in the retina.     

The light microscopic localization of substance P- and somatostatin-like immunoreactive cells in the larval tiger salamander retina

Summary Light microscopic immunocytochemistry was utilized to localize the populations of substance P (SP)- and somatostatin (SOM)-like immunoreactive cells in the larval tiger salamander retina. Of 104 SP-immunostained cells observed, 82% were Type 1 amacrine cells. Another 8% of the SP-cells were classified as Type 2 amacrine cells, while 10% of the SP-cells had their cell bodies located in the ganglion cell layer and were designated as displaced amacrine cells. Each type of SP-like immunoreactive cell was observed in the central and peripheral retina. SP-immunopositive processes were observed in the inner plexiform layer as a sparse plexus in sublamina 1 and as a denser network of fibers in sublamina 5. Seventy-eight percent of the 110 somatostatin-immunopositive cells observed were designated as Type 1 amacrine cells. Another 12% of SOM-cells were classified as displaced amacrine cells, while only two SOM-immunopositive Type 2 amacrine cells were observed. Nine percent of the SOM-cells were designated as interplexiform cells, based on their giving rise to processes distributing in the outer plexiform layer as well as processes ramifying in the inner plexiform layer. Each type of SOM-immunoreactive cell was observed in the central and peripheral retina, with the exception of the Type 2 amacrine cells, whose somas were only found in the central retina. Lastly, SOM-immunopositive processes in the inner plexiform layer appeared as a fine plexus in sublamina 1 and as a somewhat denser network of fibers in sublamina 5.     

Somatostatin-immunoreactive amacrine cells of chicken retina: retinal mosaic, ultrastructural features, and light-driven variations in peptide metabolism

Somatostatin-like immunoreactive amacrine cells of the chicken retina have been characterized by immunohistochemistry at the light and electron microscope levels. The cell bodies were set back from the junction of the inner nuclear and inner plexiform layers, and prominent fibre plexuses were found in sublaminas 1 and 3-5 of the inner plexiform layer. The cells were distributed across the retinal surface with a centroperipheral gradient of cell density. Locally, the cells were organized in a non-random mosaic. Ultrastructurally, immunohistochemical reaction product was found throughout the cytoplasm of the cell bodies, particularly associated with membranous structures, including the cytoplasmic surfaces of the Golgi apparatus, and within large dense-core vesicles. In dendritic varicosities in the inner plexiform layer, reaction product was associated with the external surfaces of small, clear synaptic vesicles. The synaptic relationships of the somatostatin-immunoreactive terminals in sublamina 1 were distinct from those in sublaminas 3-5. Those in sublamina 1 received input predominantly, possibly exclusively, from bipolar cells. Feedback synapses onto bipolar terminals or to the other amacrine cell process at a synaptic dyad were observed. In sublaminas 3-5, input came predominantly, possibly exclusively, from other, non-immunoreactive amacrine cells, and output was primarily onto other amacrine cells. No synaptic contacts with ganglion cells or with other somatostatin-immunoreactive amacrine cells were identified. Changes in levels of somatostatin-like immunoreactivity in retinas of chicks kept on 12:12 light:dark cycles were detected by radioimmunoassay, and by light and electron microscopic immunohistochemistry. Levels of retinal somatostatin-like immunoreactivity increased in the light and decreased in the dark. The changes appear to be light-driven rather than circadian, since with prolonged exposure to light or dark, the levels of somatostatin-like immunoreactivity continued to increase or decrease until plateaus were reached. The light-driven change in levels of somatostatin-like immunoreactivity may be related to the predominance of bipolar input to the immunoreactive processes in sublamina 1 of the inner plexiform layer. The reduction in peptide levels in the dark may indicate greater release of somatostatin-like immunoreactivity from the amacrine cells in the dark, resulting in an inability of peptide synthesis to keep pace with breakdown. In the light, release of somatostatin-like immunoreactivity may be lower, leading to a net synthesis of peptide.     

A system of corticotropin releasing factor-containing amacrine cells in the rat retina

Immunohistochemical processing of Long-Evans retina wholemounts using an antiserum directed against rat, human corticotropin releasing factor revealed a group of immunoreactive amacrine cells. Two subpopulations could be distinguished based primarily on the location of their cell bodies. One subpopulation had cell bodies situated along the junction of the inner nuclear layer and the inner plexiform layer. The other subpopulation had cell bodies in the ganglion cell layer. The latter was judged to be displaced amacrine cells since double-label experiments indicated that the pattern of corticotropin releasing factor-like immunoreactive staining in the ganglion cell layer did not coincide with that of ganglion cells labeled retrogradely with fluorogold. Corticotropin releasing factor-like immunoreactive amacrine cells on either side of the inner plexiform layer emitted processes which ramified extensively in sublamina 5 and, to a lesser degree, in sublamina 4. A minority of these cells also sent a single process to ramify in sublamina 1. Throughout the retina, corticotropin releasing factor-like immunoreactive cells were distributed relatively evenly, with a tendency to peak in the superior temporal region. Despite the anatomical classification into two subpopulations, it is proposed that the corticotropin releasing factor-like immunoreactive cells are functionally one system, influencing preferentially synaptic interactions associated with the inner half of the inner plexiform layer. The results of this study provide anatomical basis for further investigations of corticotropin releasing factor as a putative peptidergic neurotransmitter in the retina.     

Development of NADPH-diaphorase cells in the rat's retina

This study has examined the development of cells in the rat retina which contain nicotinamide adenine dinucleotide phosphate (NADPH) diaphorase. NADPH-diaphorase cells were first detected at postnatal day (P) 3, in somata located in the inner part of the cytoblast layer (CBL). At this age, NADPH-diaphorase reactivity was also seen in weakly labelled fibers in the presumptive outer plexiform layer (OPL). By P5, the somata of most labelled cells were in the inner part of the inner nuclear layer (INL), and by P11, their processes had spread extensively within the inner plexiform layer (IPL). By P25, there was a striking change in the pattern of NADPH-diaphorase reactivity. First, cells had lost reactivity from their large and extensive dendrites and second, there was a distinct reduction in the diameters of labelled somata. Thus, NADPH-diaphorase reactivity was most prominent during the period of synaptogenesis in the IPL. Labelled cells at P3 numbered 120 and were largely found at the superior margin of the retina. By P11, their total number had increased to the adult value of about 3400 and their density was highest in peripheral retina. With further development, the differential expansion of the retina appeared to lower the peripheral densities, resulting in an approximately uniform distribution by adulthood.     

Neuronal and glial cell types revealed by NADPH-diaphorase histochemistry in the retina of a teleost fish, the grass goby ( Zosterisessor ophiocephalus , Perciformes, Gobiidae)

The grass goby is a mud-burrowing fish with a rich retinal vasculature appropriate to its hypoxic habitat. NADPH-diaphorase histochemistry was performed on retinal sections and wholemounts to reveal cells that contain nitric oxide synthase and so may be presumed to synthesise nitric oxide, a gaseous intercellular messenger with many roles including vasodilation. Structures that were consistently stained by this method included cone ellipsoids, horizontal cells, Müller cells and their processes, large displaced ganglion cells in the inner nuclear layer (identified by their axons), large interstitial ganglion cells in the inner plexiform layer, and capillary endothelial cells. In wholemounts, horizontal cells were seen to form a regular pattern, contacting each other at their dendritic terminals. Some cells in the ganglion cell layer were weakly stained, but stained bipolar and amacrine cells were not seen. The diaphorase-positive large ganglion cells all formed large, sparsely branched dendritic trees, arborizing near the scleral border of the inner plexiform layer. The displaced and interstitial cells seemed to belong to distinct morphological types, the interstitial cells having smaller somata and trees. Analysis of their spatial distributions in one representative retina confirmed this: the displaced cells formed a highly regular mosaic with a mean spacing (nearest-neighbour distance) of 303 μm, whereas the interstitial cells formed a separate mosaic, almost as regular but with a smaller mean spacing of 193 μm, rising to 217 μm in a sample that excluded the area retinae temporalis. Spatial correlogram analysis showed that these two mosaics were spatially independent. Nitric oxide probably has many roles in the retina. The presence of its synthetic enzyme in Müller cells, which communicate with retinal blood vessels, is consistent with a role in the control of retinal blood flow. Its function in large, mosaic-forming retinal ganglion cells is unknown. Accepted: 29 April 1999     

Neuronal and glial cell types revealed by NADPH-diaphorase histochemistry in the retina of a teleost fish, the grass goby (Zosterisessor ophiocephalus, Perciformes, Gobiidae)

The grass goby is a mud-burrowing fish with a rich retinal vasculature appropriate to its hypoxic habitat. NADPH-diaphorase histochemistry was performed on retinal sections and wholemounts to reveal cells that contain nitric oxide synthase and so may be presumed to synthesise nitric oxide, a gaseous intercellular messenger with many roles including vasodilation. Structures that were consistently stained by this method included cone ellipsoids, horizontal cells, Müller cells and their processes, large displaced ganglion cells in the inner nuclear layer (identified by their axons), large interstitial ganglion cells in the inner plexiform layer, and capillary endothelial cells. In wholemounts, horizontal cells were seen to form a regular pattern, contacting each other at their dendritic terminals. Some cells in the ganglion cell layer were weakly stained, but stained bipolar and amacrine cells were not seen. The diaphorase-positive large ganglion cells all formed large, sparsely branched dendritic trees, arborizing near the scleral border of the inner plexiform layer. The displaced and interstitial cells seemed to belong to distinct morphological types, the interstitial cells having smaller somata and trees. Analysis of their spatial distributions in one representative retina confirmed this: the displaced cells formed a highly regular mosaic with a mean spacing (nearest-neighbour distance) of 303 µm, whereas the interstitial cells formed a separate mosaic, almost as regular but with a smaller mean spacing of 193 µm, rising to 217 µm in a sample that excluded the area retinae temporalis. Spatial correlogram analysis showed that these two mosaics were spatially independent. Nitric oxide probably has many roles in the retina. The presence of its synthetic enzyme in Müller cells, which communicate with retinal blood vessels, is consistent with a role in the control of retinal blood flow. Its function in large, mosaic-forming retinal ganglion cells is unknown.