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Neurotransmitters Made Easy: Chemistry and Addiction

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Neurotransmitters Made Easy: Chemistry and Addiction Neurotransmitters Made Easy: Chemistry and Addiction Brad Lander PhD, LICDC Clinical Director / Psychologist Talbot Hall - Addiction Medicine at The Ohio State University Wexner Medical Center Brain’s switching station Key Point #1 Converts short-term memory Integrates messages to long-term memory Thinking and mood are Vigilance, fear, directs attention, controlled by brain fight-flight-fright response chemicals Executive functioning (neurotransmitters) Regulates homeostasis functions (Hunger, thirst, sex, sleep, body temperature) •1 Two Functions •Excitatory - excitability of a nerve cell • Inhibitory – Slows down activity Key Point #2 We are born with genetically determined receptor sensitivity Taken from Fred Von Stieff, MD, 2012. Brain in Balance, Ghost River Images •2 Serotonin 5-hydroxytryptamine (5-HT) • Well-being • Calm mood •Self-regulation – Sleep, appetite, libido • Social bonding •Empathy Glutamate • Excites other neurons • Opposed by GABA • Associative learning • Associative memory •3 GABA gamma-aminobutyric acid • Slows activity of other neurons • Opposes glutamate • Allows calming from fear created in the amygdala Norepinephrine/ Dopamine (DA) noradrenaline -(NE) •Pleasure • Warning/vigilance – Food, water, sex •Alarm • Reinforcement • Fight – flight – fright • Motor control • Decreases nerve pain •4 Acetylcholine (Ach) Nicotine • Sympathetic nervous system • acetylcholine, noradrenalin, & dopamine levels and, at higher doses serotonin & • Memory (rote) opiate levels • Attention • Increases alertness and energy • Speeds nerve transmission “volume control” • Peripheral nerves, Internal organs, and muscle/nerve • Profile changes from stimulant to connection sedative/pain killer with increasing dosages Endocannabinoid Opiate • Movement • Analgesia • Cognition •Sedation •Memory • Decrease rate of body functions •Pain perception • Appetite Endorphin & Factors Affecting Enkephalin Neurotransmitter Systems •Diet • Endogenous morphine • Body states (fatigue, hunger, illness) • Reduce pain •Events • Euphoria & well-being • Thoughts • Transmission of pain impulses • Drugs/medicines •Hormones •5 Key Point #2 We are born with genetically determined receptor sensitivity (Temperament vs. Personality) Mood Thought Reinforcement Attention Movement Creative, High-energy Depression Mood Thought Reinforcement Attention Movement Mood Thought Reinforcement Attention Movement Schizophrenia ADD Mood Thought Reinforcement Attention Movement Mood Thought Reinforcement Attention Movement •6 Parkinson’s Disease Eight Neurotransmitter Systems Mood Thought Reinforcement Attention Movement 29 primary subtypes 83 variations Associated Mental Disorders 83 variations Serotonin Depression GABA Anxiety disorder Glutamate OCD/PTSD Dopamine Psychosis Acetylcholine Alzheimer’s disease Endocannabinoid Amotivational syndrome Opiate Chronic pain disorder •7 Predisposition for Addiction Alcoholic Family Tree 1 • Serotonin deficiency • B57 rats Alcoholic Family Tree 2 Drugs Affecting Serotonin Well-being •Ecstasy Calm mood •MDMA Self-regulation •LSD Sleep, appetite, •Cocaine libido Social bonding Empathy Drugs Affecting GABA Drugs Affecting Glutamate Slows activity of • Alcohol Excites other • Phencyclidine other neurons neurons (PCP) • Benzodiazepines Opposes Opposed by • Barbiturates •Ketamine glutamate GABA • Dextromethorphan Allows calming Associative (DMT) from fear created learning in the amygdala Associative memory •8 Drugs Affecting Dopamine Drugs Affecting Norepinephrine Pleasure •Cocaine Warning/vigilance •Cocaine Reinforcement • Amphetamine Alarm • Methamphetamine Motor initiation • Methamphet- Fight – flight - fright amine Decreases nerve pain Drugs Affecting Acetylcholine Drugs Affecting Endocannabinoid Sympathetic • Nicotine • Movement •Tetrahydrocan- nabinol (THC) nervous system • Cognition Memory (rote) •Memory Attention • Pain control Peripheral nerves • Appetite and Internal organs Drugs Affecting Opiate Analgesia •Morphine A person’s drug of Sedation •Hydrocodone choice is the one Decrease rate of •Oxycodone body functions •Heroin that lines up best •Codeine with the receptors • Methadone •Fentanyl •Tramadol •9 Key Point #3 Drug use is motivated by “correcting deficits” and Feeling better Joe Mood Thought Reinforcement Attention Movement •10 Joe + Meth Jane Mood Thought Reinforcement Attention Movement Mood Thought Reinforcement Attention Movement Jane + Meth Key Point #4 Affecting any one system affects many other systems Mood Thought Reinforcement Attention Movement - + •11 + + + - + + + - + + Key Point #5 + + + Tolerance is the down- regulation of neurons trying to “right“ the drug- + - created imbalance + •12 •13 Key Point #6 Key Point #7 Withdrawal is the up- Treatment Involves regulation process of attention to undoing tolerance neurotransmitter systems •14 Change neurotransmitter Two Types balance •Diet • Amino acid – from food – Glutamate, GABA • Wellness (sleep, exercise, relaxation) • Environment • Biogenic – made in the brain – Dopamine, serotonin, • Thoughts norepinephrine, endorphin • Medication Phenylalanine fish, poultry, meat, eggs Medications for Serotonin Tyrosine legumes, cheese, milk, Selective serotonin uptake L-phenylalanine tofu, fruits, L-Tyrosine DOPA vegetables inhibitors (SSRIs) L-DOPA vitamins C, E • Prozac, Paxil, Celexa, Lexapro Dopamine ginseng Monoamines oxidase inhibitor nettles (MAOI) Norepinephrine red clover dandelion • Parnate, Nardil, Marplan peppermint Epinephrine •15 Dopamine • Abilify • Wellbutrin • Haldol • Gabapentin •Tramadol Schizophrenia Haldol DA1 DA2 DA4 5TH1 5TH2 DA1 DA2 DA4 5TH1 5TH2 •16 Seroquil DA1 DA2 DA4 5TH1 5TH2 DA1 DA2 DA4 5TH1 5TH2 Abilify DA1 DA2 DA4 5TH1 5TH2 DA1 DA2 DA4 5TH1 5TH2 Opiate Partial agonists •Buprenorphine Suboxone, Subutex Full agonist •Methadone Antagonist •Naltrexone, ReVia, Vivitrol •17 Points to Remember Points to Remember 1. Thinking and mood are controlled by 5. Tolerance is the down-regulation of brain chemicals neurons trying to “right “ the drug- 2. We are born with genetically created imbalance determined receptor sensitivity 6. Withdrawal is the up-regulation 3. Drug use is motivated by “correcting process of undoing tolerance deficits” 7. Treatment Involves attention to 4. Affecting any one system affects neurotransmitter systems many other systems References • Psychopharmacology: Drugs, the Brain, and Behavior. Jerrold S. Meyer &, Linda F. Quenzer. Sinauer Associates, 2005. • Brain In Balance: Understanding the Genetics and Neurochemistry Behind Addiction and Sobriety. Fredrick Von Stieff M.D. Kenyon Hill Publishing, 2012. • The Secret Life of the Brain. Richard Restak, M.D. Joseph Henry Press, 2001. •18.
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