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Amacrine Cells
In the anatomy of the eye, amacrine cells are interneurons in the retina. They are named , because of their short neuronal processes. Amacrine cells are inhibitory neurons which project their dendritic arbors onto the inner plexiform layer (IPL). They interact with retinal ganglion cells and bipolar cells. Structure Amacrine cells operate at the inner plexiform layer (IPL), the second synaptic retinal layer where bipolar cells and retinal ganglion cells form synapses. There are at least 33 different subtypes of amacrine cells based just on their dendrite morphology and stratification. Like horizontal cells, amacrine cells work laterally, but whereas horizontal cells are connected to the output of rod and cone cells, amacrine cells affect the output from bipolar cells, and are often more specialized. Each type of amacrine cell releases one or several neurotransmitters where it connects with other cells. They are often classified by the width of their field of connection ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xenopus
''Xenopus'' () (Gk., ξενος, ''xenos'' = strange, πους, ''pous'' = foot, commonly known as the clawed frog) is a genus of highly aquatic frogs native to sub-Saharan Africa. Twenty species are currently described within it. The two best-known species of this genus are '' Xenopus laevis'' and '' Xenopus tropicalis'', which are commonly studied as model organisms for developmental biology, cell biology, toxicology, neuroscience and for modelling human disease and birth defects. The genus is also known for its polyploidy, with some species having up to 12 sets of chromosomes. Characteristics ''Xenopus laevis'' is a rather inactive creature. It is incredibly hardy and can live up to 15 years. At times the ponds that ''Xenopus laevis'' is found in dry up, compelling it, in the dry season, to burrow into the mud, leaving a tunnel for air. It may lie dormant for up to a year. If the pond dries up in the rainy season, ''Xenopus laevis'' may migrate long di ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Retinal Bipolar Cells
As a part of the retina, bipolar cells exist between photoreceptors (rod cells and cone cells) and ganglion cells. They act, directly or indirectly, to transmit signals from the photoreceptors to the ganglion cells. Structure Bipolar cells are so-named as they have a central body from which two sets of processes arise. They can synapse with either rods or cones (rod/cone mixed input BCs have been found in teleost fish but not mammals), and they also accept synapses from horizontal cells. The bipolar cells then transmit the signals from the photoreceptors or the horizontal cells, and pass it on to the ganglion cells directly or indirectly (via amacrine cells). Unlike most neurons, bipolar cells communicate via graded potentials, rather than action potentials. Function Bipolar cells receive synaptic input from either rods or cones, or both rods and cones, though they are generally designated rod bipolar or cone bipolar cells. There are roughly 10 distinct forms of cone bipola ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scotopic Vision
In the study of visual perception, scotopic vision (or scotopia) is the vision of the eye under low-light conditions. The term comes from the Greek ''skotos'', meaning 'darkness', and ''-opia'', meaning 'a condition of sight'. In the human eye, cone cells are nonfunctional in low visible light. Scotopic vision is produced exclusively through rod cells, which are most sensitive to wavelengths of around 498 nm (blue-green) and are insensitive to wavelengths longer than about 640 nm. Under scotopic conditions, light incident on the retina is not encoded in terms of the spectral power distribution. Higher visual perception occurs under scotopic vision as it does under photopic vision. Retinal circuitry Of the two types of photoreceptor cells in the retina, rods dominate scotopic vision. This dominance is due to the increased sensitivity of the photopigment molecule expressed in rods, as opposed to those in cones. Rods signal light increments to rod bipolar cells which, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Retina Horizontal Cell
Horizontal cells are the laterally interconnecting neurons having cell bodies in the inner nuclear layer of the retina of vertebrate eyes. They help integrate and regulate the input from multiple photoreceptor cells. Among their functions, horizontal cells are believed to be responsible for increasing contrast via lateral inhibition and adapting both to bright and dim light conditions. Horizontal cells provide inhibitory feedback to rod and cone photoreceptors. They are thought to be important for the antagonistic center-surround property of the receptive fields of many types of retinal ganglion cells. Other retinal neurons include photoreceptor cells, bipolar cells, amacrine cells, and retinal ganglion cells. Structure Depending on the species, there are typically one or two classes of horizontal cells, with a third type sometimes proposed. Horizontal cells span across photoreceptors and summate inputs before synapsing onto photoreceptor cells. Horizontal cells may also ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MEGF10
Multiple EGF-like-domains 10 is a protein that in humans is encoded by the ''MEGF10'' gene. MEGF10 is a regulator of satellite cell myogenesis and interacts with Notch1 in myoblasts. It has been shown to be the cause of early-onset myopathy, areflexia, respiratory distress and dysphagia. MEGF10 and MEGF11, have critical roles in the formation of mosaics by two retinal interneuron subtypes, starburst amacrine cells and horizontal cells Horizontal cells are the laterally interconnecting neurons having cell bodies in the inner nuclear layer of the retina of vertebrate eyes. They help integrate and regulate the input from multiple photoreceptor cells. Among their functions, horiz ... in mice. These cells are less likely to be near neighbours of the same subtype than would occur by chance, resulting in 'exclusion zones' that separate them. Mosaic arrangements provide a mechanism to distribute each cell type evenly across the retina, ensuring that all parts of the visual field h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
AII Amacrine Cells
AII (A2) amacrine cells are a subtype of amacrine cells. Amacrine cells are neurons that exist in the retina of Mammal, mammals to assist in interpreting Photoreceptor cell, photoreceptive signals. AII amacrine cells serve the critical role of transferring light signals from Rod cell, rod photoreceptors to the retinal ganglion cells (which contain the axons of the optic nerve). The AII amacrine cells are unique because they work primarily with the vertical transmission of information, meaning they connect the Bipolar neuron, bipolar and Ganglion cell, ganglion cells. Other amacrine cells primarily assist with horizontal pathways, meaning they connect similar types of Neuron, neurons. Amacrine II cells also work very similarly to rod photoreceptors in terms of Threshold potential, threshold (amount of stimulation needed to begin performing), saturation level (how densely they exist, and where), and spectral sensitivities (how sensitive the cell is to changes in stimulation levels). ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GlyT1
Sodium- and chloride-dependent glycine transporter 1, also known as glycine transporter 1, is a protein that in humans is encoded by the ''SLC6A9'' gene which is promising therapeutic target for treatment of diabetes and obesity. Selective inhibitors Elevation of extracellular synaptic glycine concentration by blockade of GlyT1 has been hypothesized to potentiate NMDA receptor function in vivo and to represent a rational approach for the treatment of schizophrenia and cognitive disorders. Several drug candidates have reached clinical trials. * ASP2535 * Bitopertin (RG1678), which has entered phase II trials for the treatment of schizophrenia * Iclepertin (BI 425809) by Boehringer Ingelheim which is thought to improve cognitive impairment due to schizophrenia * Org 25935 (Sch 900435) * PF-03463275 (in phase II trial) * Pesampator (PF-04958242) by Pfizer * Sarcosine which is thought to improve cognitive impairment due to schizophrenia Pathological mutations Mutations of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Choline Acetyltransferase
Choline acetyltransferase (commonly abbreviated as ChAT, but sometimes CAT) is a transferase enzyme responsible for the synthesis of the neurotransmitter acetylcholine. ChAT catalyzes the transfer of an acetyl group from the coenzyme acetyl-CoA to choline, yielding acetylcholine (ACh). ChAT is found in high concentration in cholinergic neurons, both in the central nervous system (CNS) and peripheral nervous system (PNS). As with most nerve terminal proteins, ChAT is produced in the body of the neuron and is transported to the nerve terminal, where its concentration is highest. Presence of ChAT in a nerve cell classifies this cell as a "cholinergic" neuron. In humans, the choline acetyltransferase enzyme is encoded by the ''CHAT'' gene. History Choline acetyltransferase was first described by David Nachmansohn and A. L. Machado in 1943. A German biochemist, Nachmansohn had been studying the process of nerve impulse conduction and utilization of energy-yielding chemical react ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Starburst Amacrine Cell
Starburst amacrine cells are a type of amacrine cells found in the retina. These interneurons are notable for co-releasing acetylcholine and GABA. See also List of distinct cell types in the adult human body The list of human cell types provides an enumeration and description of the various specialized cells found within the human body, highlighting their distinct functions, characteristics, and contributions to overall physiological processes. Cell ... References External links Starburst Amacrine Cellon Eyewire.org. Neurons {{neuroanatomy-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GABAergic
In molecular biology and physiology, something is GABAergic or GABAnergic if it pertains to or affects the neurotransmitter gamma-aminobutyric acid (GABA). For example, a synapse is GABAergic if it uses GABA as its neurotransmitter, and a GABAergic neuron produces GABA. A substance is GABAergic if it produces its effects via interactions with the GABA system, such as by stimulating or blocking neurotransmission. A GABAergic or GABAnergic agent is any chemical that modifies the effects of GABA in the body or brain. Some different classes of GABAergic drugs include agonists, antagonists, modulators, reuptake inhibitors and enzymes. See also * Adenosinergic * Adrenergic * Cannabinoidergic * Cholinergic * Dopaminergic Dopaminergic means "related to dopamine" (literally, "working on dopamine"), a common neurotransmitter. Dopaminergic substances or actions increase dopamine-related activity in the brain. Dopaminergic pathways, Dopaminergic brain pathways facil ... * Glutamat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neurotransmitter
A neurotransmitter is a signaling molecule secreted by a neuron to affect another cell across a Chemical synapse, synapse. The cell receiving the signal, or target cell, may be another neuron, but could also be a gland or muscle cell. Neurotransmitters are released from synaptic vesicles into the synaptic cleft where they are able to interact with neurotransmitter receptors on the target cell. Some neurotransmitters are also stored in large dense core vesicles. The neurotransmitter's effect on the target cell is determined by the receptor it binds to. Many neurotransmitters are synthesized from simple and plentiful precursors such as amino acids, which are readily available and often require a small number of biosynthetic steps for conversion. Neurotransmitters are essential to the function of complex neural systems. The exact number of unique neurotransmitters in humans is unknown, but more than 100 have been identified. Common neurotransmitters include Glutamate (neurotransmi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
