Confocal microscopic study of glial-vascular relationships in the retinas of pigmented rats

Zahs, Kathleen R.; Wang, Teng

doi:10.1002/1096-9861(20000108)429:2<253::aid-cne6>3.0.co;2-s

Cited by 30 publications

(22 citation statements)

References 75 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In addition, we have shown that only perivascular astroglia express the transporter, indicating a specialized function for the different astrocytes within the nerve fiber layer. Perivascular astroglia are intricately related to the development of inner retinal vessels (57) and have recently been linked to regulation of communication within the nerve fiber layer (48). Our identification of the CRT in the retinal pigmented epithelium indicates that creatine can also be obtained from the choroidal circulation.…”

Section: Discussionmentioning

confidence: 79%

“…To determine whether astrocytes of the nerve fiber layer expressed CRT, we labeled the retina with GFAP. In a vertical section of the rat retina, it is difficult to show the symmetrical stellate form of GFAP-positive astrocytes encountered outside the optic nerve area (41,57). However, GFAP labeling of the short radiating processes of astrocytes (Fig.…”

Section: Specificity Of Crt Antibodies By Western Blotting Of Membranmentioning

confidence: 99%

See 1 more Smart Citation

Creatine transporter localization in developing and adult retina: importance of creatine to retinal function

Acosta¹,

Kalloniatis²,

Christie³

2005

American Journal of Physiology-Cell Physiology

View full text Add to dashboard Cite

Creatine and phosphocreatine are required to maintain ATP needed for normal retinal function and development. The aim of the present study was to determine the distribution of the creatine transporter (CRT) to gain insight to how creatine is transported into the retina. An affinity-purified antibody raised against the CRT was applied to adult vertebrate retinas and to mouse retina during development. Confocal microscopy was used to identify the localization pattern as well as co-localization patterns with a range of retinal neurochemical markers. Strong labeling of the CRT was seen in the photoreceptor inner segments in all species studied and labeling of a variety of inner neuronal cells (amacrine, bipolar, and ganglion cells), the retinal nerve fibers and sites of creatine transport into the retina (retinal pigment epithelium, inner retinal blood vessels, and perivascular astrocytes). The CRT was not expressed in Müller cells of any of the species studied. The lack of labeling of Müller cells suggests that neurons are independent of this glial cell in accumulating creatine. During mouse retinal development, expression of the CRT progressively increased throughout the retina until approximately postnatal day 10, with a subsequent decrease. Comparison of the distribution patterns of the CRT in vascular and avascular vertebrate retinas and studies of the mouse retina during development indicate that creatine and phosphocreatine are important for ATP homeostasis.

show abstract

Section: Discussionmentioning

confidence: 79%

Section: Specificity Of Crt Antibodies By Western Blotting Of Membranmentioning

confidence: 99%

Creatine transporter localization in developing and adult retina: importance of creatine to retinal function

Acosta¹,

Kalloniatis²,

Christie³

2005

American Journal of Physiology-Cell Physiology

View full text Add to dashboard Cite

show abstract

“…In the retina, astrocytes are found exclusively in the nerve fibre layer. Zahs and Wu (2001) demonstrated morphologically that there are at least two subclasses of astrocyte within the retina: intervascular astrocytes, which are located between the major arterioles, and vascular astrocytes, which have an Fig. 4 Immunofluorescent labelling of EAAT4 (A) and GLAST (B) and areas that colocalize (C).…”

Section: Discussionmentioning

confidence: 99%

“…Astrocytes are confined to those retinae that have an inner retinal blood supply and have an intricate relationship with retinal blood vessels (Zahs and Wu 2001). They are thought to be important for development of the retinal vasculature and maintaining the blood retinal barrier.…”

Section: Discussionmentioning

confidence: 99%

Localization and expression of the glutamate transporter, excitatory amino acid transporter 4, within astrocytes of the rat retina

Ward

Jobling

Puthussery

et al. 2004

Cell and Tissue Research

View full text Add to dashboard Cite

Mechanisms for the removal of glutamate are vital for maintaining normal function of the retina. Five excitatory amino acid transporters have been characterized to date from neuronal tissue, all of which are expressed within the retina except excitatory amino acid transporter 4 (EAAT4). In this study we examined the expression and localization of the glutamate transporter EAAT4 in the rat retina using RT-PCR and immunocytochemistry. RT-PCR using rat EAAT4 specific primers revealed a prominent 296-bp product in the retina, cortex and cerebellum. The identity of the EAAT4 fragment was confirmed by DNA sequencing. We examined the tissue expression levels of EAAT4 in cortex, retina and cerebellum using real-time PCR. The highest expression level was found in the cerebellum. Expression in the cortex was approximately 3.1% that of the cerebellum and the retina was found to have approximately 0.8% the total cerebellar EAAT4 content. In order to examine the specific cell types within the retina that express EAAT4, we performed immunocytochemistry using a rat EAAT4 specific antiserum. Cellular processes within the nerve fibre layer of the retina were intensely labelled for EAAT4. Double labelling EAAT4 with glial fibrillary acidic protein (GFAP) revealed extensive colocalization indicating that EAAT4 is localized within astrocytes within the retina. Double labelling of EAAT4 and the glutamate transporter EAAT1 (GLAST) revealed extensive colocalization suggesting that astrocytes in the retina express at least two types of glutamate transporters. These results suggest that astrocytes within the retina are well placed to provide mechanisms for glutamate removal as well as controlling cellular excitability.

show abstract

“…They are actively involved in uptake and degradation of the amino acid neurotransmitters, glutamate and GABA, are involved in shuttling energy metabolites to neurons and are also important for maintenance of the blood-retinal barrier [9][10][11]. Astrocytes are intricately linked with the vasculature and have processes within the nerve fibre and ganglion cell layers [12]. The function of astrocytes within the retina is not clearly defined, although they do express glutamate transporters such as GLAST and EAAT4 [13,14].…”

Section: Introductionmentioning

confidence: 99%

Glutamate uptake in retinal glial cells during diabetes

et al. 2005

View full text Add to dashboard Cite

Aims: Glutamate recycling is a major function of retinal Müller cells. The aim of this study was to evaluate the expression and function of glutamate transporters during diabetes. Methods: Sprague-Dawley rats were rendered diabetic by a single dose of streptozotocin (50 mg/kg). Following 12 weeks of diabetes, immunolocalisation and mRNA expression of the two glial cell transporters, GLAST and EAAT4 were evaluated using indirect immunofluorescence and real-time PCR. The function of glutamate transport was investigated at 1, 4 and 12 weeks following induction of diabetes by measuring the level of uptake of the non-metabolisable glutamate analogue, D-aspartate, into Müller cells. Results: There was no difference in the localisation of either GLAST or EAAT4 during diabetes. Although there was a small apparent increase in expression of both GLAST and EAAT4 in diabetic retinae compared with controls this was not statistically significant. At 1, 4 and 12 weeks following diabetes, D-aspartate immunoreactivity was significantly increased in Müller cells of diabetic rats compared to controls (p<0.001). The EC 50 was found to increase by 0.304 log units in diabetic Müller cells compared with controls, suggesting that glutamate uptake is twice as efficient. Conclusions: These data suggest that there are alterations in glutamate transport during diabetes. However, these changes are unlikely to play a significant role in glutamate-induced neuronal excitoxicity during diabetes. These results suggest that although Müller cells undergo gliosis at an early stage of diabetes, one of the most important functions for maintaining normal retinal function is preserved within the retina.

show abstract

Confocal microscopic study of glial-vascular relationships in the retinas of pigmented rats

Cited by 30 publications

References 75 publications

Creatine transporter localization in developing and adult retina: importance of creatine to retinal function

Creatine transporter localization in developing and adult retina: importance of creatine to retinal function

Localization and expression of the glutamate transporter, excitatory amino acid transporter 4, within astrocytes of the rat retina

Glutamate uptake in retinal glial cells during diabetes

Contact Info

Product

Resources

About