Chapter 2- Review of Terms & Chart

Chapter 2 questions How com nicotine be a miser and as Review of Terms: Agonist Antagonist enhance the function of a neurotransmitter Block the actions of a neurotransmitter Tolerance: The need to gradually increase the dose of a drug to produce the some effects peripheral tolerance includes the changes in the systems responsible for absorption, metabolism, distribution and excretion of drugs which results in the nead to face mare drugs Neuronal Teverance the changes in the brain's tightly regulated chemistry that neurons undergo to compensate for the addition of a drug Witharawa A person 16 considered addicted if they show both symprams of tolerance & withdrawal The adversive reaction that occurs when substanice use is terminacted ما Symptoms include desire to obtain the drug and me cxpression peychological sympromes (depression, anxiety) and physiological symptoms (pain, changes in autonomy nervous System) Exnergence of a new sondition or re-emergence of a previous condition Neural mechanisms of Addiction criteria to be addictive: 1). A drug must produce euphoria, pressure or relief from an aversive mativation (4.9 relief fhen pain or phychiatric candiren) 21. A drug must directly or indirectly increase neural activity in the mesacorticalimbic dopamine pathway This pathway is responsible for producing pressure in the brain and its activation is considered to be a primang reason addicts use a given drug. 5). A drug must produce a neural tolerance * Drugs are more livery to be akuned if they can be taken socia Via a hallinvasive route of administration (2-9 arai maring με τηκότιση) κ A drug must produce seif administration self medicating 5) upon termination of drug use, terise withdrawal symptoms must cour that include intense drug seeking or craving. lo). Dependency not to fem better, to feri normal they depend on the drug to portorm mormal doing sumities TOLERANCE Neurons Tightly regulate their membrane patentials, nutrient supplies from gliel cars, and the removal of waste products an imbalance can lead to temporary inactivation or apoptosis (cell death). specific mechanism of tolerance may vary depending on class of a drug in generas the process is very rapid often occurring within 24 hours of a single administration Ineroine can be in as litere as 5 min) جا since herdink therance occurs so rapidly, the dase needed to prassice cuphoria can exceed the lethal dose within a few administrations bne method of tolerance is the down requsation of receptor number Reause thee if of receptors so the drug has fewer ways to stimulats the neurom Le accomplisaned by activation of merabotrapic recepters that unen activates then an t-partan mediated responses that ineptiracle other receptors by capping associated con channels or decoupling the receptor from its effector another synaptic change is an enlargement of the gap Junorton saws down neurotransmission reduction in ayrinesis & revesse of neurotransmitter and up regretion of termination mecanisms. stimulant Depressant Nicotine receptor Subtype of Acetylcholine inotropic receptor nicotine, is a stimulant so it decreases the # of receptors, therefore NOT an addictive ar produces antagonism. The inhibition of the HpA and HPT Axis has two functions: جا ). The HPA asis is the system that causes the release of glucocorticoides so inhibition of Hon asis shuts off the stress response or aces to provide negative featback 1 2). Innibition of the HPT axis is designed to conserve energy results in the production of thyroid hormone thurmuns ATP to teicast neat →HPT exίς παρs muntain your body temperaturs Addictive Drugs Innibit motivation All addictive drugs either directly or indirectly produce euphoria by causing an increase in activity in the mesocorticolumbic copamine pathway The net effect is to increase dopamine mediated inhibition of motivation and the suarsequent pleasure that is produced when motivation is inhibited. Dopaminergic psychostimulants Block the Dopamine transporter All known dopamine receptors are merabotropic and All inhibitory * • As one of the catecholamines, dopamine is also removed from the synapse via reuptake. One of the actions of both the amphetamines and sacaine 1s to wark as reuptake inhibitors by blocking the dopamine transportsz pratun why are they called psychostimulants if they increase dopamine dependent inhibition? Dopamine is also used in the Di and D2 motor pamways. It is important to now normes voluntary movements require that dopamine activity must be balanced in the Di and Da motor pathways to produce normal locomotor activity. Too little dopamine in the motor pathways and you get parkinsons disease which is characterized by slow movements. Too much dopamine in the motor pathways produces unconeralled hisper kinetic behaviors (rapid and wild morsements) associated with muningtons desease Lo when a person takes cocaine or amphetamine, they do not target Just the reward pathways. Instead each alle drives the motor pathways and produces hypermotivity CTP GDP adenylyl vlase protein kinase AMP ATP Figure 3. The dopamine synapse. The 21 and 25 receptors turn on G-protein semulated expression of gene respomes that inhithit the neuron. The D2 and 14 pers activate G-proteins that activate channels. Because these channels allow & Sons fore, the neuron is beperpolarized. The 113 neptor activates a G-protein that turn off the synthesis and release of depamime from the peexynaptic dll. The degiamine transporter (DTT) belings dopamin hack into the presynaptic cell for mactivation and recycling reuptake). hinon PAP