BIOL 3322 1nd Edition Lecture 7I. Drugs & hormones influence brain & behavior II. Psychopharmacology – psychoactive drugs – exert effect by influencing synaptic chemical signalingIII. Routes of drug administrationa. Injection – SQ, IM, IV i. IV 2nd fasted to the brainii. IM & SQ slower more sustainedb. Oral – safe, economical i. Goes into the stomach, then liver, heart, lungs, then to the brainc. Inhalation – drug into the brain very quickly IV. Blood brain barriera. Right charge, right size & lipid soluble to pass V. Area posterma – entry of toxic substances that induce vomitingVI. Pituitary gland – entry of chemicals that influence pituitary hormonesVII. Pineal gland – entry of chemicals that affect day & night cycles VIII. Eliminating drugs from the body a. Catabolize in kidneys liver & intestinesb. Excreted by urine feces sweat breast milk & exhaled in the airIX. Agonist – substance that enhances function of a synapse X. Antagonist – substance that blocks/decreases function of a synapseXI. Drug action synapses a. Synthesis b. Storage c. Release d. Receptor interactione. Inactivationf. Reuptakeg. DegradationXII. Acetylcholine (Ach)a. Agonist i. Choline – rich diet increases Ach ii. Black widow spider venom promotes release iii. Nicotine stimulates receptors iv. Physostigmine & organophosphates block inactivationb. Antagonist i. Botulin toxin blocks releaseii. Curare blocks receptorsXIII. Tolerance a. Learned behavior results when a response to a stimulus weakens with repeated presentations metabolic tolerance These notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.b. Repeated use is reducing amount of drug at target receptors c. Body gets more efficient at metabolizing substancesd. Cellular – brain cells neurons adjuste. Learned – person learns to cope with having substancef. Cross – tolerance XIV. Sensitization a. Occasional drug user may experience an increased responsiveness to successive equal doses b. Tolerance generally develops with repeated use of a drugc. Sensitization much more likely to develop with occasional used. Comparable to allergic non – sensitive – get stronger second useXV. Sensitization - enhancement of drug effects after repeated administration of same drugs dosingXVI. Classification of psychoactive drugsa. Antianxiety i. Barbiturates – high risk ii. Benzodiazepines – more usefull & safer1. Long term not good2. Short term good3. Sedation sleep relief from anxiety 4. Too much = anesthesia coma death5. Easy to ODiii. Works by GABA receptor 1. Influx of chloride (Cl-) ions hyperpolarizes neuron (IPSP)2. Help GABA do its job better; less likely that AP will fire3. OD bc also decreases respiration – breathingb. Dissociative anesthetics – PCP/ketaminei. Alerted states ii. Distortionsiii. Work by NMDA receptor – noncompetitive receptor free agent iv. NMDA receptors – inotropic receptors for the excitatory neurotransmitter