Neurotransmitters and drugs

Signaling molecules in the nervous system

Homework due: NTM – Job analogy

• Neurotransmitter worksheet• For each NTM on the sheet, describe a job that is similar

Neurotransmitter (NT):A chemical in our nervous system that transmits info between neurons

Copy the chart on the board and fill in the name, E or I, effects and drug interactions for the following NTMs:

• Serotonin• Dopamine• GABA• Glutamate• Norepinephrine• Acetylcholine

Which neurotransmitter?• Jodie is depressed. She most likely has low levels of _________• John is a stressed out business man. To reduce his anxiety he takes

Xanax, a medication that increases ________, and calms his brain.• LSD causes hallucinations, which are similar to dreams. They are

caused by _________• Botox freezes facial muscles. It blocks the release of ________• Samuel is a schizophrenic homeless man. He hears voices, is

paranoid and has twitchy movements. He has elevated levels of ______

• James is a meth addict. He just smoked some. He hears voices, is paranoid and has twitchy movements. He has elevated levels of ______

• Thanksgiving dinner makes you sleepy. That’s because turkey containts a chemical precursor to _________, which regulates sleep

• Prozac and other antidepressants prevent reuptake of ________, thus keeping it in the synapse where it is active

What kind of neurotransmitter are you?

• http://archives.drugabuse.gov/havefun/what_neurotransmitter_popup.php

Agonists and AntagonistsHow many ways can an NTM be increased or decreased in the images below?

Increasing and decreasing the effect of NTMs

Agonist:A drug (or poison) increases activity of a NTM. How?• Mimics shape• Prevents reuptake by pre-synaptic neuron• Blocks enzymes that break down NTM in synapseAntagonist:

A drug (or poison) that reduces NTM activity• Blocks release of NTM from its terminal button• Blocks receptor on post synaptic dendrite

Agonist or antagonist?• Botox blocks the release of ACh, which temporarily

paralyzes facial muscles (and reduces wrinkles)• Pfizer just created a new drug improves mood by binding

to serotonin receptors and stimulating an action potential• Synthesis inhibitors are chemicals that slow down the

creation of a neurotransmitter molecules• Prozac and other antidepressants are SSRI drugs: selective

serotonin reuptake inhibitors• Black widow spider poison causes neurons to release ALL

their ACh, depleting their supply. Then they have none, preventing the cell from functioning (causes death)

Different neurotransmitters do different things!Acetylcholine (ACh):NT that affects learning and memory (in the brain), and movement (in muscles)Alzheimer’s patients have lower levels of ACh.

This American Life: A Trip Down Memory Lane

Botulinum poison:An antagonist that blocks the release of Ach, can paralyze diaphragm musclesand stop breathing

Botox: Before and After

Curare:Antagonist for Ach, leads to paralysis.S. American Indians use it for hunting.

Black widow spider poison:Ach agonist, causes flood of Ach, the Ach runs out

S. American Indian Hunters

Dopamine:Reward and motivationRewarding/pleasurable: eating, drinking, sexMotor control over voluntary Low levels Parkinson’s

Parkinson’s treatments can cause symptoms of schizophrenia (losing touch with reality, hallucinations, false beliefs, etc.)

Michael J Fox Interview

This American Life: Schizophrenia

Amphetamines and cocaine:Dopamine ____________ “High” arousal state followed by a crash

Other examples:Painkillers, caffeine, nicotine

Serotonin:Emotional states/mood, impulsiveness, sleep and dreaming

Norepinephrine:Alertness, higher mood level, focus and concentration

Low levels of these NTs are related to depression, sadness/anxiety, food cravings, and aggressive behavior.

Antidepressants are ____________ for them, as well as drugs for eating disorders, OCD, and obesity.

Ex. Prozac, Paxil, Zoloft, Cymbalta, Pristiq, and Effexor

GABA (gamma-aminobutyric acid):the main inhibitory NT, keeps brain from getting too aroused/over-excitedLowers arousal/anxiety and helps regulate movement

Antianxiety drugs (tranquilizers) are ____________ for GABA

Glutamate:the main excitatory NT, memory storage and pain perception

High levels can cause neuron death, low levels can cause comaGlutamate may be linked to schizophrenia

Endorphins:NT involved in pain relief and pleasure

Higher endorphins levels have been found in runners post-marathons and in women during childbirth

Morphine and heroin mimic endorphins, and cause a release of dopamine

Is it linked to acupuncture?

Reading quiz1. Which neurotransmitter is involved in

1. Muscle movement2. Pleasure/reward3. Mood4. Sleep/dreams/hallucinations

2. An agonist/antagonist reduces the effect of neurotransmitters in the synapse (which one?)

3. Botulinum toxin blocks the release of Ach. This makes it an agonist/antagonist

Drugs

• Drugs are chemicals that interact with neurotransmitters • Agonistic or antagonistic mechanisms• Can be taken orally, inhaled, smoked, injected or through the skin• Illegal and therefore unregulated• Contaminated/diluted• Dangerous

Source: Substance Abuse and Mental Health Services Administration, 2005

Socratic Seminar Rules

• Call people by name• Attack ideas not people• Yes, and… always add to a comment, it’s not enough to simply agree• 3 before me. Give others a chance to speak• Don’t hog the mic

You will turn in your partner evaluation and be graded on how thoughtfully you assess your partner, plus your 2 homework questions.

Explore: Drugs of abuseDue next class if not finished today

• Watch 3 or 4 animations, your choice which ones.• Flow chart: profile of a drug. Pick ONE.• Make a graphic organizer/flowchart that shows the

following:• Names (include several) drug is known by• Context: typical place this drug is used, or typical person who

uses it• Effects/sensations experienced• Risks/dangers• One statistic or historical anecdote about this drug (look up

online)

http://learn.genetics.utah.edu/content/addiction/abuse/

Choose 4 of the drugs on mouse party and see how they work internally, at the synapse. For each one, write the following:

1) Name of drug 2) Neurotransmitters it interacts with3) Agonist or antagonist4) Labeled diagram of the synapse, the drug, neurotransmitters and receptors.5) Regions/circuits of the brain affected by this drug

http://learn.genetics.utah.edu/content/addiction/drugs/mouse.html

Meth – a life destroying drughttps://www.youtube.com/watch?v=T-duk-PiIXo – meth in the brain

www.methproject.org/

1) Click on the links under "get answers". Explore the site: read, watch the videos, play the games.

2) Day in the life of a meth addict. Create a profile of a person who’s addicted to meth. What is a typical day like for them? A. Write a diary excerpt of a typical day from their perspective.

3) Finally, click the link on the right "view ads" to watch some of the famous television commercials produced by the meth project.

4) Don't take meth!

10 ways drugs will ruin a date

http://www.youtube.com/watch?v=xEht8tKKwVQ&list=PL8CD42150CBB6EFA8