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Dopamine Therapy
Dopamine therapy is the regulation of levels of the neurotransmitter dopamine through the use of either agonists, or antagonists; and has been used in the treatment of disorders characterized by a dopamine imbalance. Dopamine replacement therapy (DRT) is an effective treatment for patients with decreased levels of dopamine. Often dopamine agonists, compounds that activate dopamine receptors in the absence of that receptor's physiological ligand, the neurotransmitter dopamine, are used in this therapy. DRT has been shown to reduce symptoms and increase lifespan for patients with Parkinson's disease. Dopamine regulation plays a critical role in human mental and physical health. The neurons that contain the neurotransmitter are clustered in the midbrain region in an area called the substantia nigra. In Parkinson's patients, the death of dopamine-transmitting neurons in this area leads to abnormal nerve-firing patterns that cause motor problems. Research in patients with schizophrenia in ... [...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] |
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] |
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] |
Schizophrenia
Schizophrenia is a mental disorder characterized by continuous or relapsing episodes of psychosis. Major symptoms include hallucinations (typically hearing voices), delusions, and disorganized thinking. Other symptoms include social withdrawal, decreased emotional expression, and apathy. Symptoms typically develop gradually, begin during young adulthood, and in many cases never become resolved. There is no objective diagnostic test; diagnosis is based on observed behavior, a history that includes the person's reported experiences, and reports of others familiar with the person. To be diagnosed with schizophrenia, symptoms and functional impairment need to be present for six months (DSM-5) or one month (ICD-11). Many people with schizophrenia have other mental disorders, especially substance use disorders, depressive disorders, anxiety disorders, and obsessive–compulsive disorder. About 0.3% to 0.7% of people are diagnosed with schizophrenia during their lifetime. In 2 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dopamine Agonists
A dopamine agonist (DA) is a compound that activates dopamine receptors. There are two families of dopamine receptors, D2-like and D1-like, and they are all G protein-coupled receptors. D1- and D5-receptors belong to the D1-like family and the D2-like family includes D2, D3 and D4 receptors. Dopamine agonists are primarily used to treat Parkinson's disease. They are also used, to a far lesser extent, in treating hyperprolactinemia and restless legs syndrome. They are not intended for treatment of clinical depression, and studies have shown severe detrimental side effects resulting from off-label use of dopamine agonists in treating depression, particularly in their tendency to produce impulse control disorders and extreme cases of withdrawal syndrome. Medical uses Parkinson's disease Dopamine agonists are mainly used in the treatment of Parkinson's disease. The cause of Parkinson's is not fully known but genetic factors, for example specific genetic mutations, and environment ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Levodopa
-DOPA, also known as levodopa and -3,4-dihydroxyphenylalanine, is an amino acid that is made and used as part of the normal biology of some plants and animals, including humans. Humans, as well as a portion of the other animals that utilize -DOPA, make it via biosynthesis from the amino acid -tyrosine. -DOPA is the precursor to the neurotransmitters dopamine, norepinephrine (noradrenaline), and epinephrine (adrenaline), which are collectively known as catecholamines. Furthermore, -DOPA itself mediates neurotrophic factor release by the brain and CNS. -DOPA can be manufactured and in its pure form is sold as a psychoactive drug with the INN levodopa; trade names include Sinemet, Pharmacopa, Atamet, and Stalevo. As a drug, it is used in the clinical treatment of Parkinson's disease and dopamine-responsive dystonia. -DOPA has a counterpart with opposite chirality, -DOPA. As is true for many molecules, the human body produces only one of these isomers (the -DOPA form). The enant ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dopamine Receptor D2
Dopamine receptor D2, also known as D2R, is a protein that, in humans, is encoded by the ''DRD2'' gene. After work from Paul Greengard's lab had suggested that dopamine receptors were the site of action of antipsychotic drugs, several groups, including those of Solomon Snyder and Philip Seeman used a radiolabeled antipsychotic drug to identify what is now known as the dopamine D2 receptor. The dopamine D2 receptor is the main receptor for most antipsychotic drugs. The structure of DRD2 in complex with the atypical antipsychotic risperidone has been determined. Function D2 receptors are coupled to Gi subtype of G protein. This G protein-coupled receptor inhibits adenylyl cyclase activity. In mice, regulation of D2R surface expression by the neuronal calcium sensor-1 (NCS-1) in the dentate gyrus is involved in exploration, synaptic plasticity and memory formation. Studies have shown potential roles for D2R in retrieval of fear memories in the prelimbic cortex and in discrimina ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dopamine Receptor D1
Dopamine receptor D1, also known as DRD1. It is one of the two types of D1-like receptor family - receptors D1 and D5. It is a protein that in humans is encoded by the DRD1 gene. Tissue distribution D1 receptors are the most abundant kind of dopamine receptor in the central nervous system. Northern blot and in situ hybridization show that the mRNA expression of DRD1 is highest in the dorsal striatum ( caudate and putamen) and ventral striatum (nucleus accumbens and olfactory tubercle). Lower levels occur in the basolateral amygdala, cerebral cortex, septum, thalamus, and hypothalamus. Function D1 receptors regulate the memory, learning, and the growth of neurons, also is used in the reward system and locomotor activity, mediating some behaviors and modulating dopamine receptor D2-mediated events. They play a role in addiction by facilitating the gene expression changes that occur in the nucleus accumbens during addiction. They are Gs/a coupled and can stimulate neuron ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dopamine Releasing Agents
A dopamine releasing agent (DRA) is a type of drug which induces the release of dopamine in the body and/or brain. No selective DRAs are currently known. Many releasing agents of both dopamine and norepinephrine (norepinephrine–dopamine releasing agents, or NDRAs) and of serotonin, norepinephrine, and dopamine are known ( serotonin-norepinephrine-dopamine releasing agents, or SNDRAs), however. Serotonin–dopamine releasing agents are much rarer and are not selective for monoamine release. Examples of NDRAs include amphetamine and methamphetamine, and an example of an SNDRA is MDMA. The most selective dopamine releaser is 4-methylaminorex, but it also has considerable activity as a norepinephrine releaser. These drugs are frequently used for Recreational drug use, recreational purposes and encountered as substance abuse, drugs of abuse. A closely related type of drug is a dopamine reuptake inhibitor (DRI). Various selective DRIs are known, in contrast to the case of DRAs. It is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
