Heroin Anna Markarova Julia Bataille Georgia Klein
Heroin • Comes from the seedpod of the opium poppy plant • Processed from morphine • It’s a depressant that inhibits the central nervous system and affects the brains ability to feel pain • Usually appears as white or brown powder or as a black sticky substance • Can be injected, sorted/sniffed, or smoked
Presynaptic Neuron (non-activated) Before opioid receptor activation, Calcium channels are open and the K channels are closed. The seven transmembrane receptors are G protein coupled receptors
Presynaptic Neuron(activated) • Once morphine is attached the K channels open and Calcium channels close • Morphine has a greater affinity for the Mu opioid receptor than the gamma and delta • Decrease in glutamine, Ach, NE, 5-HT, and substance P
Cell Signaling Pathways • Once heroin enters the brain it is converted into morphine and attaches to receptors in the brain known as opioid receptors • These receptors are found in many areas of the brain, especially those involved in the perception of pain and reward, also found in brain stem • Opioid receptors are classified into two categories, classical and non-classic • Opioid receptors are 7 transmembrane receptors
Types of Receptors • Opioid receptors are G protein-coupled receptors (GPCRs) with opiates as ligands • Large protein family of receptors that sense molecules outside the cell and active signal transduction pathways • A ligand is a chemical signal that binds to a receptor protein • GABA inhibits the release of dopamine Heroin mimics this and inhibits the release of GABA • 3 receptors types: • Mu: Functions: analgesia, antidepressant, physical dependence • Delta:Functions: anticonvulsant effects, dysphoria, miosis, sedation • Kappa:Functions:respiratory depression, euphoria, physical dependence
Signal Transduction Pathways • GPCRs are the surface receptors that alter intracellular functions to create a response. • Receptors changes receptor protein in some way, which causes transduction. • Heroin binds to the receptors and blocks GABA from being released • Dopamine is released since GABA isn’t there to inhibit its production • Dopamine is released and attaches to the dopamine receptors.
Effects of Heroin • Morphine mimics endorphins, which are responsible for reducing pain, causing sleepiness, and feelings of pleasure. They can be released by pain, exercise, orgasm, or excitement • Activation of opioid receptors associate with analgesia, sedation, euphoria, physical dependence, and respiratory depression. • Heroin abuse is associated with serious health conditions, fatal overdose, abortion, HIV/AIDS and hepatitis. • Chronic users may develop collapsed veins, infection of the heart lining and valves, liver or kidney disorders.
Correct Mechanism • Dopamine naturally occurs in the body • It’s released when native opiate binds to a receptor site and continues on the same way to release dopamine
Direction of Research Research has found a way to reduce the chances of addiction to heroin by blocking the TLR4 because it helps to increase the effect of endorphins. http://www.foxnews.com/health/2012/08/15/researches-find-way-to-block-heroin-morphine-addiction/