Although biological cells are mostly transparent, they phase objects that differ in shape and refractive index. Any image is projected through layers of randomly oriented will normally be distorted by refraction, reflection, scattering. Counterintuitively, the retina vertebrate eye inverted with respect to its optical function light must pass several tissue before reaching light-detecting photoreceptor cells. Here we report on specific properties glial present retina, which might contribute...

Abstract Glial cell‐mediated potassium and glutamate homeostases play important roles in the regulation of neuronal excitability. Diminished buffering capabilities astrocytes result hyperexcitability neurons abnormal synaptic transmission. The role different K + channels maintaining membrane potential cortical has not yet been definitively determined due to lack specific channel blockers. purpose present study was assess inward‐rectifying subunit Kir4.1 on fluxes, uptake cultured rat using...

Inwardly rectifying potassium channel Kir4.1 is critical for glial function, control of neuronal excitability, and systemic K(+) homeostasis. Novel mutations in have been associated with EAST/SeSAME syndrome, characterized by mental retardation, ataxia, seizures, hearing loss, renal salt waste. Patients are homozygous R65P, G77R, C140R or T164I; compound heterozygous A167V/R297C R65P/R199Stop, a deletion the C-terminal half protein. We investigated functional significance these radiotracer...

Polyamines are ubiquitous organic cations implicated in many physiological processes. Because they positively charged at pH, carrier-mediated systems necessary for effective membrane permeation, but the identity of specific polyamine transporter proteins eukaryotic cells remains unclear. Polyspecific cation transporters (OCTs) interact with natural and xenobiotic monovalent have been reported to transport dicationic compounds, including short putrescine. In this study, we used Xenopus...

KCNJ10 encodes subunits of inward rectifying potassium (Kir) channel Kir4.1 found predominantly in glial cells within the brain. Genetic inactivation these channels glia impairs extracellular K(+) and glutamate clearance produces a seizure phenotype. In both mice humans, polymorphisms mutations gene have been associated with susceptibility. The purpose present study was to determine whether there are differences Kir activity potassium- glutamate-buffering capabilities between astrocytes from...

Spermine (SPM) and spermidine, endogenous polyamines with the ability to modulate various ion channels receptors in brain, exert neuroprotective, antidepressant, antioxidant, other effects vivo such as increasing longevity. These are preferably accumulated astrocytes, we hypothesized that SPM increases glial intercellular communication by interacting gap junctions. The results obtained situ, using Lucifer yellow propagation astrocytic syncitium of 21-25-day-old rat CA1 hippocampal slices,...

Accumulating evidence indicate that astrocytes are essential players of the excitatory and inhibitory signaling during normal epileptiform activity via uptake release gliotransmitters, ions, other substances. Polyamines can be regarded as gliotransmitters since they almost exclusively stored in released by various mechanisms. The polyamine putrescine (PUT) is utilized to synthesize GABA, which also from provide tonic inhibition on neurons. spermine (SPM), synthesized form PUT through...

Abstract Tandem‐pore domain (2P‐domain) K + ‐channels regulate neuronal excitability, but their function in glia, particularly, retinal glial cells, is unclear. We have previously demonstrated the immunocytochemical localization of 2P‐domain channels TASK‐1 and TASK‐2 Müller cells amphibians. The purpose present study was to determine whether these were functional, by employing whole‐cell recording from frog mammalian (guinea pig, rat mouse) confocal microscopy monitor swelling cells....

Astrocyte endfeet surround brain blood vessels and can play a role in the delivery of therapeutic drugs for Parkinson’s disease. However, there is no previous evidence presence LAT transporter L -DOPA astrocytes except culture. Using systemic administration combination patch clamp, histochemistry confocal microscopy we found that accumulated mainly astrocyte cell bodies, astrocytic surrounding vessels, pericytes. In slices: (1) were exposed to ASP + , fluorescent monoamine analog MPP ; (2)...

Glioblastoma is one of the most aggressive and fatal brain cancers due to highly invasive nature glioma cells. Microglia infiltrate tumors and, therefore, make up an important component microenvironment. In tumor environment, microglia release factors that lead degradation extracellular matrix stimulate signaling pathways promote cell invasion. present study, we demonstrated can migration through a mechanism independent degradation. Using western blot analysis, found upregulation proline...

There is recent evidence that polyamines such as spermine (spm) and spermidine (spd) may act endogenous modulators of the activity inwardly rectifying K+ channels. This type channels abundantly expressed by retinal glial (Muller) cells where they are involved in important cell functions clearance excess extracellular ions. prompted us to study following questions, i) do mammalian Muller contain spm/spd?; ii) possess enzymes (e.g., ornithine decarboxylase, ODC) necessary produce iii) does...

There is recent evidence that polyamines such as spermine (spm) and spermidine (spd) may act endogenous modulators of the activity inwardly rectifying K+ channels. This type channels abundantly expressed by retinal glial (Müller) cells where they are involved in important cell functions clearance excess extracellular ions. prompted us to study following questions, i) do mammalian Müller contain spm/spd?; ii) possess enzymes (e.g., ornithine decarboxylase, ODC) necessary produce iii) does...

Whereas kainate (KA)-induced neurodegeneration has been intensively investigated, the contribution of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors (AMPARs) in neuronal Ca2+ overload ([Ca2+]i) is still controversial. Using imaging and patch-clamp techniques, we found different types entry cultured rat cortical neurons. The presence extracellular solution was required to generate [Ca2+]i responses 30 μM N-methyl-d-aspartate (NMDA) or KA. dynamics NMDA-induced were fast, while...

Polyamines (PAs), such as spermine and spermidine, modulate the activity of numerous receptors channels in central nervous system (CNS) are stored glial cells; however, little attention has been paid to their role regulation connexin (Cx)-based gap junction channels. We have previously shown that PAs facilitate diffusion Lucifer Yellow through astrocytic junctions acute brain slices; therefore, we hypothesized can regulate Cx43-mediated (as most abundant Cx astrocytes) junctional...

Birds which possess high visual acuity, such as eagles and falcons, are known to have retinas with a deep conically curved central foveal pit. There been different attempts explain the importance of this particular shape fovea in resolution. Recently, function Müller cells "light fibers" was discovered, showing how endfeet trap light then transfer it single cone photoreceptor. Here we describe line walls pit Pied Flycatcher, cell body extends its processes towards individual cones, forming...