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Tuberoinfundibular Pathway
The tuberoinfundibular pathway refers to a population of dopamine neurons that project from the arcuate nucleus ( the "infundibular nucleus") in the tuberal region of the hypothalamus to the median eminence. It is one of the four major dopamine pathways in the brain. Dopamine released at this site inhibits the secretion of prolactin from anterior pituitary gland lactotrophs by binding to D2 receptors. Some antipsychotic drugs block dopamine in the tuberoinfundibular pathway, which can cause an increase in the amount of prolactin in the blood (hyperprolactinemia). Other dopamine pathways Other major dopamine pathways include: * Mesocortical pathway * Mesolimbic pathway * Nigrostriatal pathway See also * Antipsychotic * 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 const ... ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tuberoinfundibular Pathway
The tuberoinfundibular pathway refers to a population of dopamine neurons that project from the arcuate nucleus ( the "infundibular nucleus") in the tuberal region of the hypothalamus to the median eminence. It is one of the four major dopamine pathways in the brain. Dopamine released at this site inhibits the secretion of prolactin from anterior pituitary gland lactotrophs by binding to D2 receptors. Some antipsychotic drugs block dopamine in the tuberoinfundibular pathway, which can cause an increase in the amount of prolactin in the blood (hyperprolactinemia). Other dopamine pathways Other major dopamine pathways include: * Mesocortical pathway * Mesolimbic pathway * Nigrostriatal pathway See also * Antipsychotic * 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 const ... ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dopamine Pathways
Dopamine (DA, a contraction of 3,4-dihydroxyphenethylamine) is a neuromodulatory molecule that plays several important roles in cells. It is an 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 chemical, L-DOPA, which is 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 dopamine pathways, one of which plays a major role in the motivational component of reward-motivated behavior. The anticipation of most types of rewards increases the level of dopamine in the brain, and many addi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypothalamus
The hypothalamus () is a part of the brain that contains a number of small nuclei with a variety of functions. One of the most important functions is to link the nervous system to the endocrine system via the pituitary gland. The hypothalamus is located below the thalamus and is part of the limbic system. In the terminology of neuroanatomy, it forms the ventral part of the diencephalon. All vertebrate brains contain a hypothalamus. In humans, it is the size of an almond. The hypothalamus is responsible for regulating certain metabolic processes and other activities of the autonomic nervous system. It synthesizes and secretes certain neurohormones, called releasing hormones or hypothalamic hormones, and these in turn stimulate or inhibit the secretion of hormones from the pituitary gland. The hypothalamus controls body temperature, hunger, important aspects of parenting and maternal attachment behaviours, thirst, fatigue, sleep, and circadian rhythms. Structure T ... [...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] |
Antipsychotic
Antipsychotics, also known as neuroleptics, are a class of Psychiatric medication, psychotropic medication primarily used to manage psychosis (including delusions, hallucinations, paranoia or disordered thought), principally in schizophrenia but also in a range of other psychotic disorders. They are also the mainstay together with mood stabilizers in the treatment of bipolar disorder. Prior research has shown that use of any antipsychotic is associated with smaller brain tissue volumes, including white matter reduction and that this brain shrinkage is dose dependent and time dependent. A more recent controlled trial suggests that second generation antipsychotics combined with intensive psychosocial therapy may potentially prevent pallidal brain volume loss in first episode psychosis. The use of antipsychotics may result in many unwanted side effects such as Extrapyramidal symptoms, involuntary movement disorders, gynecomastia, impotence, weight gain and metabolic syndrome. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nigrostriatal Pathway
The nigrostriatal pathway is a bilateral dopaminergic pathway in the brain that connects the substantia nigra pars compacta (SNc) in the midbrain with the dorsal striatum (i.e., the caudate nucleus and putamen) in the forebrain. It is one of the four major dopamine pathways in the brain, and is critical in the production of movement as part of a system called the basal ganglia motor loop. Dopaminergic neurons of this pathway release dopamine from axon terminals that synapse onto GABAergic medium spiny neurons (MSNs), also known as spiny projection neurons (SPNs), located in the striatum. Degeneration of dopaminergic neurons in the SNc is one of the main pathological features of Parkinson's disease, leading to a marked reduction in dopamine function and the symptomatic motor deficits of Parkinson's disease including hypokinesia, tremors, rigidity, and postural imbalance. Anatomy The connection between the substantia nigra pars compacta and the dorsal striatum is mediated via dopa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mesolimbic Pathway
The mesolimbic pathway, sometimes referred to as the reward pathway, is a dopaminergic pathway in the brain. The pathway connects the ventral tegmental area in the midbrain to the ventral striatum of the basal ganglia in the forebrain. The ventral striatum includes the nucleus accumbens and the olfactory tubercle. The release of dopamine from the mesolimbic pathway into the nucleus accumbens regulates incentive salience (e.g. motivation and desire for rewarding stimuli) and facilitates reinforcement and reward-related motor function learning; it may also play a role in the subjective perception of pleasure. The dysregulation of the mesolimbic pathway and its output neurons in the nucleus accumbens plays a significant role in the development and maintenance of an addiction. Anatomy The mesolimbic pathway is a collection of dopaminergic (i.e., dopamine-releasing) neurons that project from the ventral tegmental area (VTA) to the ventral striatum, which includes the nucleus accumben ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mesocortical Pathway
The mesocortical pathway is a dopaminergic pathway that connects the ventral tegmentum to the prefrontal cortex. It is one of the four major dopamine pathways in the brain. It is essential to the normal cognitive function of the dorsolateral prefrontal cortex (part of the frontal lobe), and is thought to be involved in cognitive control, motivation, and emotional response. This pathway may be the brain system that is abnormal or functioning abnormally in psychoses, such as schizophrenia.Diaz, Jaime. How Drugs Influence Behavior. Englewood Cliffs: Prentice Hall, 1996. It is thought to be associated with the negative symptoms of schizophrenia, which include avolition, alogia and flat affect. This pathway is closely associated with the mesolimbic pathway, which is also known as the mesolimbic reward pathway. Other dopamine pathways Other major dopamine pathways include: * mesolimbic pathway * nigrostriatal pathway * tuberoinfundibular pathway See also * Dopamine * Schizophrenia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hyperprolactinemia
Hyperprolactinaemia is the presence of abnormally high levels of prolactin in the blood. Normal levels average to about 13 ng/mL in women, and 5 ng/mL in men, with an upper normal limit of serum prolactin levels being 15-25 ng/mL for both. When the fasting levels of prolactin in blood exceed this upper limit, hyperprolactinemia is indicated. Prolactin (PRL) is a peptide hormone produced by lactotroph cells in the anterior pituitary gland. PRL is involved in lactation after pregnancy and plays a vital role in breast development. Hyperprolactinemia may cause galactorrhea (production and spontaneous flow of breast milk), infertility, and disruptions in the normal menstrual period in women; as well as hypogonadism, infertility and erectile dysfunction in men. Although hyperprolactinemia can result from normal physiological changes during pregnancy and breastfeeding, it can also be caused by other etiologies. For example, high prolactin levels could result from diseas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arcuate Nucleus
The arcuate nucleus of the hypothalamus (also known as ARH, ARC, or infundibular nucleus) is an aggregation of neurons in the mediobasal hypothalamus, adjacent to the third ventricle and the median eminence. The arcuate nucleus includes several important and diverse populations of neurons that help mediate different neuroendocrine and physiological functions, including neuroendocrine neurons, centrally projecting neurons, and astrocytes. The populations of neurons found in the arcuate nucleus are based on the hormones they secrete or interact with and are responsible for hypothalamic function, such as regulating hormones released from the pituitary gland or secreting their own hormones. Neurons in this region are also responsible for integrating information and providing inputs to other nuclei in the hypothalamus or inputs to areas outside this region of the brain. These neurons, generated from the ventral part of the periventricular epithelium during embryonic development, locat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antipsychotic
Antipsychotics, also known as neuroleptics, are a class of Psychiatric medication, psychotropic medication primarily used to manage psychosis (including delusions, hallucinations, paranoia or disordered thought), principally in schizophrenia but also in a range of other psychotic disorders. They are also the mainstay together with mood stabilizers in the treatment of bipolar disorder. Prior research has shown that use of any antipsychotic is associated with smaller brain tissue volumes, including white matter reduction and that this brain shrinkage is dose dependent and time dependent. A more recent controlled trial suggests that second generation antipsychotics combined with intensive psychosocial therapy may potentially prevent pallidal brain volume loss in first episode psychosis. The use of antipsychotics may result in many unwanted side effects such as Extrapyramidal symptoms, involuntary movement disorders, gynecomastia, impotence, weight gain and metabolic syndrome. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anterior Pituitary
A major organ of the endocrine system, the anterior pituitary (also called the adenohypophysis or pars anterior) is the glandular, anterior lobe that together with the posterior lobe (posterior pituitary, or the neurohypophysis) makes up the pituitary gland (hypophysis). The anterior pituitary regulates several physiological processes, including stress, growth, reproduction, and lactation. Proper functioning of the anterior pituitary and of the organs it regulates can often be ascertained via blood tests that measure hormone levels. Structure The pituitary gland sits in a protective bony enclosure called the sella turcica (''Turkish chair/saddle''). It is composed of three lobes: the anterior, intermediate, and posterior lobes. In many animals, these lobes are distinct. However, in humans, the intermediate lobe is but a few cell layers thick and indistinct; as a result, it is often considered part of the anterior pituitary. In all animals, the fleshy, glandular anterior pitui ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
