Neurotransmitters and Brain Structure: A Comprehensive Guide, Exams of Nursing

Download Neurotransmitters and Brain Structure: A Comprehensive Guide and more Exams Nursing in PDF only on Docsity! PSYCHOPHARMACOLOGY AND NEUROTHERAPEUTICS (160 questions and answers) GRADED A+ 2024 UPDATE Neuron - SOLUTION basic unit of the nervous system Soma - SOLUTION cell body of the neuron, houses the nucleus Nucleus - SOLUTION contains genomic DNA Dendrites - SOLUTION Branchlike parts of a neuron that are specialized to receive information. Axon - SOLUTION A threadlike extension of a neuron that carries nerve impulses away from the cell body. Node of Ranvier - SOLUTION A gap between successive segments of the myelin sheath where the axon membrane is exposed. Schwann cells - SOLUTION Supporting cells of the peripheral nervous system responsible for the formation of myelin. axon terminal - SOLUTION End of branch of axon; contains chemical messengers called neurotransmitters Human brain is organized into - SOLUTION cerebral cortex, brainstem, subcortical structures and cerebellum Fundamental premise of psychiatric neuroscience - SOLUTION people with major mental illness suffer as a result of abnormal brain function intermediate phenotype - SOLUTION disease trait in the path of pathogens; from genetic predisposition to manifestation. Identifying intermediate phenotypes is helpful because - SOLUTION identifying intermediate phenotypes with high heritability is helpful in delineating the genetics of the disorder. endophenotypes - SOLUTION Bio-behavioral abnormalities that are linked to genetic and neurobiological causes of mental illness. Neuro imaging - living brain - SOLUTION best modern tool for examining pathophysiology of mental illness. Can quantitatively measure morphometry, metabolism and functional activity. spatial resolution r/t neuro imaging - SOLUTION limited in examining microscopic changes implicated in psychiatric illness What is neurophysiology? - SOLUTION electrical activity in the brain; provides excellent spatial and temporal resolution. EEG - SOLUTION An amplified recording of the waves of electrical activity that sweep across the brain's surface. These waves are measured by electrodes placed on the scalp. ERP - SOLUTION event related potential MEG - SOLUTION magnetoencephalography, measures changes in magnetic fields on the surface of the scalp produced by changes in patterns of neural activity TMS (transcranial magnetic stimulation) - SOLUTION a treatment that involves placing a powerful pulsed magnet over a person's scalp, which alters neuronal activity in the brain brain stimulation therapy - SOLUTION This type of therapy is used to treat depression through electroshock therapy. Can be invasive or non-invasive. Neuropathology - SOLUTION Study of characteristics and origins of diseases and their effects on the nervous system post mortem Adoption, twin, and familial segregation studies prove many psychiatric d/o are - SOLUTION heritable forward genetics - SOLUTION Traditional approach to the study of gene function that begins with a phenotype (a mutant organism) and proceeds to a gene that encodes the phenotype. Ramon y Cajal and the Neuron Doctrine (1906) - SOLUTION neurons act as physically discrete units within the brain, communicating with each other through specialized junctions. neuron axon length - SOLUTION highly variable short axon length - SOLUTION inhibitory, inter-neurons that make only local connections longer axon length - SOLUTION cortical projection neurons must reach contralateral hemisphere or down the spinal cord. motor and sensory neurons may have axons that are several feet long Classifying Neurons - SOLUTION structure histology function electrophysiology neurotransmitter type Classifying Neurons by Structure - SOLUTION projection local-inter neuron Histology of neurons - SOLUTION Bipolar multipolar unipolar Function of neurons - SOLUTION excitatory inhibitory modulatory Electrophysiology of neuron - SOLUTION tonic phasic fast-spiking There are 10 times more ___________ than neurons - SOLUTION Glia Glia means - SOLUTION glue Glia support neuronal functioning by - SOLUTION supplying nutrition maintaining homeostasis stabilizing synapses myelinating axons Glia play an important role in ___________________ - SOLUTION synaptic transmission Microglia (CNS) - SOLUTION Remove cell debris, wastes, and pathogens by phagocytosis Macroglial cells - SOLUTION astrocytes and oligodendrocytes Astrocytes (CNS) - SOLUTION for blood brain barrier; control external environment of neurons Oligodendrocytes - SOLUTION Type of glial cell in the CNS that wrap axons in a myelin sheath. Mood d/o are associated with a decreased number of _______ in select brain regions - SOLUTION glia cells Glia and neurons are elegantly situated within the brain to facilitate - SOLUTION signaling between adjacent cells and between cells in different brain regions Neurotransmitters Amino Acids - SOLUTION Glutamate and GABA Neurotransmitters Monoamines - SOLUTION dopamine, norepinephrine, serotonin, histamine Neurotransmitters Small molecule neurotransmitter - SOLUTION Acetylcholine Neurotransmitters trigger - SOLUTION either rapid or slow effector systems second messenger system - SOLUTION mechanism by which neurotransmitters and many hormones cause a cellular response inside the cell human genome - SOLUTION cAMP PKA CAMK GSK Glutamate - SOLUTION A major excitatory neurotransmitter; involved in memory Glutamate is an ______ neurotransmitter - SOLUTION excitatory Glutamate is a - SOLUTION non essential amino acid Glutamate does not cross the - SOLUTION blood brain barrier Glutamine synthesis - SOLUTION converts glutamate and aspartate to glutamine Glutamine can not diffuse across - SOLUTION cell membranes Glutamate receptors include - SOLUTION G-protein coupled receptors and the ligand-gated receptors (NMDA, AMPA and kainate). Glutamate plays an important role in - SOLUTION learning and memory NDMA is a - SOLUTION glutamate and ion channel receptor NDMA plays a role in - SOLUTION normal and abnormal cognitive processes When activated, NDMA serves as a channel for the influx of - SOLUTION calcium ions into neurons The influx of calcium ions into the neuron relies on binding of - SOLUTION ligands - glutamine and glycine - to the receptor and depolarization of the post-synaptic membrane which causes magnesium to block the channel signaling between pre and post synaptic membranes occurs - SOLUTION simultaneously NDMA and AMPA receptors mediate - SOLUTION long term potential in hippocampus Mesocortical pathway - SOLUTION cognition, social behavior, planning, problem solving, motivation and reinforcement in learning. Negative symptoms of schizo (flat affect, apathy, lack of motivation and anhedonia) have been associated with diminished activity in the mesocortical tract. Mesolimbic pathway - SOLUTION associated with memory, emotion, arousal, and pleasure. Excess activity implicated in positive symptoms of schizophrenia Tuberoinfundibular pathway - SOLUTION Connects the *hypothalamus and the pituitary gland* Digestion, metabolism, hunger, thirst, temperature control, and sexual arousal Is responsible for *dopamine-dependent prolactin inhibition*. Antipsychotic action here cause an increase in prolactin, leading to galactorrhea, disruption of menstrual cycle, and sexual dysfunction. dopamine is synthesized from - SOLUTION Tyrosine Vesicular dopamine can be catabolized by - SOLUTION MAO MAOIs - SOLUTION monoamine oxidase inhibitors MAO's are present in - SOLUTION Liver and GI tract and degrades dietary amines such as tyramine and phenylethylamine HTN crisis can occur if phenylethylamine is - SOLUTION systemically absorbed. Patients must avoid foods that contain it. COMT - SOLUTION catechol-O-methyltransferase DAT - SOLUTION dopamine transporter COMT and DAT clear - SOLUTION dopamine from the synaptic cleft In the midbrain, DAT plays a more important role than - SOLUTION COMT In prefrontal cortex, COMT - SOLUTION dominates Patients with 1 more copies of met allele (COMT genes) have greater concentrations of - SOLUTION prefrontal dopamine Increased dopamine causes - SOLUTION mania and schizophrenia Decreased dopamine causes - SOLUTION Parkinson's and depression Norepinephrine is a - SOLUTION monoamine Nor epinephrine (NE) - SOLUTION the neurotransmitter used by the sympathetic division of the autonomic nervous system at the post- ganglionic organ-level (synapse) Nor-epinephrine cell bodies are located in the - SOLUTION locus coeruleus (located in the pons near the 4th ventricle) Ventral collection of nor-epinephrine neurons projects into the - SOLUTION hypothalamus and other CNS sites Dorsal collection of nor epinephrine neurons projects to the - SOLUTION cerebral cortex, hippocampus, cerebellum, spinal cord Nor-epinephrine overlaps with dopamine in regards to - SOLUTION synthesis and degradation Nor-epinephrine is degraded by - SOLUTION MAO and COMT 3 types of adrenoreceptors (No-epinephrine) - SOLUTION alpha 1, alpha 2, and beta Why is clonidine used in opiate withdrawal? - SOLUTION dampons adrenergic tone by activating CNS alpha 2 receptors. inhibits cAMP and locus coeruleus neurons initiating calming, sedating effects Serotonin - SOLUTION Affects mood, hunger, sleep and arousal. Undersupply linked to depression. Serotonin is synthesized - SOLUTION raphe nucleus raphe nuclei - SOLUTION a group of nuclei located in the reticular formation of the medulla, pons, and midbrain, situated along the midline; contain serotonergic neurons VMAT (vesicular monoamine transporter) - SOLUTION transports dopa and Epi in to secretory vesicles in chromaffin cells serotonin transporter - SOLUTION target of selective serotonin reuptake inhibitors used in treating major depressive disorder and certain anxiety disorders Drugs that block SERT - SOLUTION prolong serotonin's actions i.e. SSRI Drugs of abuse prolong serotonin's actions by - SOLUTION blocking SERT. examples are cocaine, amphetamines, and MDMA Acetylcholine (ACh) - SOLUTION A neurotransmitter that enables learning and memory and also triggers muscle contraction AcH is a target of psychopharmacology for - SOLUTION dementia and movement disorders AcH plays a important role - SOLUTION in central and peripheral neurophysiology 2 classes of ACh receptors - SOLUTION nicotinic and muscarinic nicotinic receptors - SOLUTION On all ANS postganglionic neurons, in the adrenal medulla, and at neuromuscular junctions of skeletal muscle Excitatory when ACh binding occurs muscarinic receptors - SOLUTION Cholinergic receptors that are located postsynaptically in the effector organs such as smooth muscle, cardiac muscle, and glands supplied by parasympathetic fibers. Histamine receptors - SOLUTION H1, H2, H3