Dopamine Pathways psychopharmacology ppt

Dopamine Pathways psychopharmacology ppt

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  DOPAMINE PATHWAYS Aqsa shahid Assignmentwriter Contact :[email protected]
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  NIGROSTRAIATAL PATHWAY Anatomy Dopamine neuronsproject from Substantia nigra to dorsal striatum. Functions: 1. Motor control: regulation of voluntary movements 2. Movement coordination: balance, posture, and locomotion
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  Components: 1. Substantia nigrapars compacta (SNc): dopamine-producing 2. Striatum: receives dopamine input from SNc 3. Caudate nucleus: The caudate nucleus (CN; plural “caudate nuclei”) is a paired,“C”-shaped subcortical structure which lies deep inside the brain near the thalamus. It plays a critical role in various higher neurological functions.Also involved in movement planning. 4. Putamen:The putamen is a round structure situated at the base of the forebrain. It is involved in movement regulation and coordination.
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  Diseases and Disorders: 1.Parkinson’s disease: degeneration of SNc dopamine neurons 2. Huntington’s disease: damage to striatal neurons 3. Dyskinesia: abnormal movement disorders 4. Addiction: dysfunction in reward processing. 5. Dystonia: abnormal posterual movement
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  INFUNDIBULAR PATHWAY The tuberoinfundibularpathway is one of the major dopamine pathways inthe brain originating from the hypothalamus. The tuberoinfundibular pathway refers to a population of dopamine neurons that project from the arcuate nucleus(a.k.a. the "infundibular nucleus") in the tuberal region of the hypothalamus to the median eminence.[1] 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 dopamine receptor D2.
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  Location: Arcute nucleus.the Tuberoinfundibularpathway begins in the arctute nucleus of the hypothalamus. Characteristics: Dopamine inhibits prolactin (PRL)Within Tuberoinfundibular pathway, the release of dopamine naturally inhibit the secretion of prolactin from the interior pituitary gland. Defects: AntipsychoticsThe use of antipsychotics contribute to a dopamine blockade, therefore with dopamine blockade, prolactin level can increase and contribute to hyperprolactinemia. Increased Prolactin: If there is a defect or the inhibition of the tuberoinfundibular pathway, this inhibits the release of dopamine. With dopamine inhibited, this leads to increased levels of prolactin
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  Sexual Dysfunction: Defects ofthe tuberoinfundibular pathway will lead to decreased dopamineand increased levels of prolactin. Hyperprolactinemia can lead to conditions such as sexual ovstunction. decreased libido, ovnecomastia, and galactorrhea. Decreased Libido: Refers to reduction in sexual desire. Galactorrhea: Galactorrhea is a condition characterized by the spontaneous flow of milk or a milk-like discharge from the breasts, not associated with breastfeeding or pregnancy. Gynecomastia: Gynecomastia is a condition in which males experience an enlargement of breast tissues.
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  OVERVIEW OF THEINCERTO- HYPOTHALAMIC PATHWAY A neural pathway linking the zona incerta (ZI) and the hypothalamus Anatomy: Zona Incerta (ZI): Subthalamic region involved in motor, sensory, and arousal functions. Hypothalamus : Integrative center for autonomic, endocrine, and behavioral processes.
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  FUNCTIONS 1-Regulation of StressResponses:This pathway is involved in the modulation of stress-related behaviors and physiological responses. It helps coordinate the body's reaction to stress through its influence on the hypothalamus, which controls the release of stress hormones. 2. Feeding Behavior:The pathway also plays a role in appetite regulation. It can influence hunger and satiety signals, affecting how and when we eat 3. Reproductive Functions:The incerto-hypothalamic pathway is involved in reproductive behaviors and hormonal regulation, impacting processes like mating and menstrual cycles. 4. Sleep-Wake Cycle: There is evidence that this pathway may also contribute to the regulation of sleep patterns and wakefulness.
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  DYSREGULATION Dysregulation of theincerto-hypothalamic pathway has been implicated in various neurological and psychiatric disorders, including: 1. _Eating disorders 2. _Anxiety disorders 3. _Depressive disorders 4. _Sleep disorders 5. _Metabolic disorders