Section 11 - Drug Abuse

Click to edit Master title style Click to edit Master text styles Second level Third level Fourth level Fifth level Click to edit Master title style Click to edit Master text styles Second level Third level Fourth level Fifth level Click to edit Master text styles Second level Third level Fourth level Fifth level Principles of Pharmacology and Toxicology (BIOL3020) Section 11 Drug Abuse and Toxicological Effects of Drugs Rang et al 2006 Pharmacology (Chapter 43) Stine and Brown (2006) Principles of Toxicology x x CNS Stimulates Caffeine Amphetamines and cocaine Cocaine and amphetamines acts by blocking reuptake of dopamine, norepinephrine and serotonin Drug Use Most recreational drugs are neuroactive Caffeine Inhibits Adenosine Receptors Ad iGP Extracellular Intracellular AC adenosine receptor Ca2 Ca2 Neuron Caffeine Opium 20 alkaloids found in the juice of the opium poppy Primary one is morphine Others include codine and papaverine Synthetic opioids include heroin Heroin formed by reacting morphine with acetic anhydride or acetyl chloride Opioid Receptors Mediate pain and other pathways that produce feelings of euphoria Endogenous neurotransmitters (enkephalins, endorphins, dynorphins) Opioids Opioids are addictive Tolerance will develop Overdose causes pupillary constriction, depression of respiration (causing death) The Opioid Receptor Opioid Receptor GPCR GP Ca K Inhibit adenlylate cyclase Inhibits Ca channels Opens K channels Neuronal inhibition AC Lysergic acid diethylamide (LSD) Produce distortions of perception and thinking Interacts with 5-HT receptors MDMA (ecstacy) methylenedioxymethamphetamine Acts mainly by inhibiting 5-HT uptake Psychedelic Drugs (hallucinogens) Alcohol Effects of ethanol  Effects of ethanol C  Toxicokinetics Metabolism I OH Ethanol CH3CH2OH Acetaldehyde CH3CHO ADH Metabolism II Acetaldehyde CH3CHO ALDH Acetate CH3COO- O- Metabolism III The oxidation of ethanol requires NAD as a cofactor Rate of ethanol oxidation dependent on availability of NAD Competition between ethanol and other compounds for NAD may damage cells Metabolism IV Rate is constant (not increased by concentrations in the blood) About 30 ml (1 oz) in 3 hours W W Another route of elimination of alcohol Tobacco and Nicotine (  Pharmacology of Nicotine Pharmacokinetics of Nicotine ( Harmful effects of smoking Cannabis Cannabinoid Receptors G-protein-coupled receptor family, linked to inhibition of adenylate cyclase Inhibits calcium channels and activates potassium channel function, causing inhibition of synaptic transmission. Cannabinoid Receptor GPCR GP Ca K AC Cannabinoid Receptors