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Neuromelanin
Neuromelanin (NM) is a dark pigment found in the brain which is structurally related to melanin. It is a polymer of Melanin#Eumelanin, 5,6-dihydroxyindole monomers. Neuromelanin is found in large quantities in catecholaminergic cell groups, catecholaminergic cells of the substantia nigra#Pars compacta, substantia nigra pars compacta and locus coeruleus, giving a dark color to the structures. Physical properties and structure Neuromelanin gives specific brain sections, such as the substantia nigra or the locus coeruleus, distinct color. It is a type of melanin and similar to other forms of peripheral melanin. It is insoluble in organic compounds, and can be labeled by silver staining. It is called neuromelanin because of its function and the color change that appears in tissues containing it. It contains black/brown pigmented granules. Neuromelanin is found to accumulate during aging, noticeably after the toddler, first 2–3 years of life. It is believed to protect neurons in the s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neuromelanin In A Neuron Of The Substantia Nigra
Neuromelanin (NM) is a dark pigment found in the brain which is structurally related to melanin. It is a polymer of Melanin#Eumelanin, 5,6-dihydroxyindole monomers. Neuromelanin is found in large quantities in catecholaminergic cell groups, catecholaminergic cells of the substantia nigra#Pars compacta, substantia nigra pars compacta and locus coeruleus, giving a dark color to the structures. Physical properties and structure Neuromelanin gives specific brain sections, such as the substantia nigra or the locus coeruleus, distinct color. It is a type of melanin and similar to other forms of peripheral melanin. It is insoluble in organic compounds, and can be labeled by silver staining. It is called neuromelanin because of its function and the color change that appears in tissues containing it. It contains black/brown pigmented granules. Neuromelanin is found to accumulate during aging, noticeably after the toddler, first 2–3 years of life. It is believed to protect neurons in the s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
5,6-dihydroxyindole
Melanin (; from el, μέλας, melas, black, dark) is a broad term for a group of natural pigments found in most organisms. Eumelanin is produced through a multistage chemical process known as melanogenesis, where the oxidation of the amino acid tyrosine is followed by polymerization. The melanin pigments are produced in a specialized group of cells known as melanocytes. Functionally, eumelanin serves as protection against UV radiation. There are five basic types of melanin: eumelanin, pheomelanin, neuromelanin, allomelanin and pyomelanin. The most common type is eumelanin, of which there are two types— brown eumelanin and black eumelanin. Pheomelanin, which is produced when melanocytes are malfunctioning due to derivation of the gene to its recessive format is a cysteine-derivative that contains polybenzothiazine portions that are largely responsible for the of red yellow tint given to some skin or hair colors. Neuromelanin is found in the brain. Research has been undert ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Melanin
Melanin (; from el, μέλας, melas, black, dark) is a broad term for a group of natural pigments found in most organisms. Eumelanin is produced through a multistage chemical process known as melanogenesis, where the oxidation of the amino acid tyrosine is followed by polymerization. The melanin pigments are produced in a specialized group of cells known as melanocytes. Functionally, eumelanin serves as protection against Ultraviolet, UV radiation. There are five basic types of melanin: eumelanin, pheomelanin, neuromelanin, allomelanin and pyomelanin. The most common type is eumelanin, of which there are two types— brown eumelanin and black eumelanin. Pheomelanin, which is produced when melanocytes are malfunctioning due to derivation of the gene to its recessive format is a cysteine-derivative that contains polybenzothiazine portions that are largely responsible for the of red yellow tint given to some skin or hair colors. Neuromelanin is found in the brain. Research ha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Melanin
Melanin (; from el, μέλας, melas, black, dark) is a broad term for a group of natural pigments found in most organisms. Eumelanin is produced through a multistage chemical process known as melanogenesis, where the oxidation of the amino acid tyrosine is followed by polymerization. The melanin pigments are produced in a specialized group of cells known as melanocytes. Functionally, eumelanin serves as protection against Ultraviolet, UV radiation. There are five basic types of melanin: eumelanin, pheomelanin, neuromelanin, allomelanin and pyomelanin. The most common type is eumelanin, of which there are two types— brown eumelanin and black eumelanin. Pheomelanin, which is produced when melanocytes are malfunctioning due to derivation of the gene to its recessive format is a cysteine-derivative that contains polybenzothiazine portions that are largely responsible for the of red yellow tint given to some skin or hair colors. Neuromelanin is found in the brain. Research ha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Substantia Nigra
The substantia nigra (SN) is a basal ganglia structure located in the midbrain that plays an important role in reward and movement. ''Substantia nigra'' is Latin for "black substance", reflecting the fact that parts of the substantia nigra appear darker than neighboring areas due to high levels of neuromelanin in dopaminergic neurons. Parkinson's disease is characterized by the loss of dopaminergic neurons in the substantia nigra pars compacta. Although the substantia nigra appears as a continuous band in brain sections, anatomical studies have found that it actually consists of two parts with very different connections and functions: the pars compacta (SNpc) and the pars reticulata (SNpr). The pars compacta serves mainly as a projection to the basal ganglia circuit, supplying the striatum with dopamine. The pars reticulata conveys signals from the basal ganglia to numerous other brain structures. Structure The substantia nigra, along with four other nuclei, is part ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Locus Coeruleus
The locus coeruleus () (LC), also spelled locus caeruleus or locus ceruleus, is a nucleus in the pons of the brainstem involved with physiological responses to stress and panic. It is a part of the reticular activating system. The locus coeruleus, which in Latin means "blue spot", is the principal site for brain synthesis of norepinephrine (noradrenaline). The locus coeruleus and the areas of the body affected by the norepinephrine it produces are described collectively as the locus coeruleus-noradrenergic system or LC-NA system. Norepinephrine may also be released directly into the blood from the adrenal medulla. Anatomy The locus coeruleus (LC) is located in the posterior area of the rostral pons in the lateral floor of the fourth ventricle. It is composed of mostly medium-size neurons. Melanin granules inside the neurons of the LC contribute to its blue colour. Thus, it is also known as the nucleus pigmentosus pontis, meaning "heavily pigmented nucleus of the pons." The n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Catecholamines
A catecholamine (; abbreviated CA) is a monoamine neurotransmitter, an organic compound that has a catechol (benzene with two hydroxyl side groups next to each other) and a side-chain amine. Catechol can be either a free molecule or a substituent of a larger molecule, where it represents a 1,2-dihydroxybenzene group. Catecholamines are derived from the amino acid tyrosine, which is derived from dietary sources as well as synthesis from phenylalanine. Catecholamines are water-soluble and are 50% bound to plasma proteins in circulation. Included among catecholamines are epinephrine (adrenaline), norepinephrine (noradrenaline), and dopamine. Release of the hormones epinephrine and norepinephrine from the adrenal medulla of the adrenal glands is part of the fight-or-flight response. Tyrosine is created from phenylalanine by hydroxylation by the enzyme phenylalanine hydroxylase. Tyrosine is also ingested directly from dietary protein. Catecholamine-secreting cells use several re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parkinson's Disease
Parkinson's disease (PD), or simply Parkinson's, is a long-term degenerative disorder of the central nervous system that mainly affects the motor system. The symptoms usually emerge slowly, and as the disease worsens, non-motor symptoms become more common. The most obvious early symptoms are tremor, rigidity, slowness of movement, and difficulty with walking. Cognitive and behavioral problems may also occur with depression, anxiety, and apathy occurring in many people with PD. Parkinson's disease dementia becomes common in the advanced stages of the disease. Those with Parkinson's can also have problems with their sleep and sensory systems. The motor symptoms of the disease result from the death of cells in the substantia nigra, a region of the midbrain, leading to a dopamine deficit. The cause of this cell death is poorly understood, but involves the build-up of misfolded proteins into Lewy bodies in the neurons. Collectively, the main motor symptoms are also known as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neuron
A neuron, neurone, or nerve cell is an electrically excitable cell that communicates with other cells via specialized connections called synapses. The neuron is the main component of nervous tissue in all animals except sponges and placozoa. Non-animals like plants and fungi do not have nerve cells. Neurons are typically classified into three types based on their function. Sensory neurons respond to stimuli such as touch, sound, or light that affect the cells of the sensory organs, and they send signals to the spinal cord or brain. Motor neurons receive signals from the brain and spinal cord to control everything from muscle contractions to glandular output. Interneurons connect neurons to other neurons within the same region of the brain or spinal cord. When multiple neurons are connected together, they form what is called a neural circuit. A typical neuron consists of a cell body (soma), dendrites, and a single axon. The soma is a compact structure, and the axon and dend ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pars Compacta
The pars compacta (SNpc) is a portion of the ''substantia nigra'', located in the midbrain. It is formed by dopaminergic neurons and located medial to the pars reticulata. Parkinson's disease is characterized by the death of dopaminergic neurons in this region. Anatomy In humans, the nerve cell bodies of the ''pars compacta'' are coloured black by the pigment neuromelanin. The degree of pigmentation increases with age. This pigmentation is visible as a distinctive black stripe in brain sections and is the origin of the name given to this volume of the brain. The neurons have particularly long and thick dendrites (François et al.). The ventral dendrites, particularly, go down deeply in the pars reticulata. Other similar neurons are more sparsely distributed in the midbrain and constitute "groups" with no well-defined borders, although continuous to the pars compacta, in a prerubral position. These have been given, in early works in rats (with not much respect for the anatomical ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Catecholaminergic Cell Groups
Catecholaminergic cell groups refers to collections of neurons in the central nervous system that have been demonstrated by histochemical fluorescence to contain one of the neurotransmitters dopamine or norepinephrine. Thus, it represents the combination of dopaminergic cell groups and noradrenergic cell groups. Some authors include in this category 'putative' adrenergic cell groups, collections of neurons that stain for PNMT, the enzyme that converts norepinephrine to epinephrine (adrenalin). Catecholaminergic cell groups and Parkinson's disease have an interactive relationship. Catecholaminergic neurons containing neuromelanin are more susceptible to Parkinson's related cell death than nonmelanized catecholaminergic neurons. Neuromelanin is an autoxidation byproduct of catecholamines, and it has been suggested that catecholaminergic neurons surrounded by a low density of glutathione peroxidase cells are more susceptible to degeneration in Parkinson's disease than those protected ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dopamine
Dopamine (DA, a contraction of 3,4-dihydroxyphenethylamine) is a neuromodulatory molecule that plays several important roles in cells. It is an organic compound, organic chemical of the catecholamine and phenethylamine families. Dopamine constitutes about 80% of the catecholamine content in the brain. It is an amine synthesized by removing a carboxyl group from a molecule of its precursor (chemistry), precursor chemical, L-DOPA, which is biosynthesis, synthesized in the brain and kidneys. Dopamine is also synthesized in plants and most animals. In the brain, dopamine functions as a neurotransmitter—a chemical released by neurons (nerve cells) to send signals to other nerve cells. Neurotransmitters are synthesized in specific regions of the brain, but affect many regions systemically. The brain includes several distinct dopaminergic pathway, dopamine pathways, one of which plays a major role in the motivational component of reward system, reward-motivated behavior. The anticipa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
