4.03- Drugs Change the Way Neurons Communicate

BMT II

Unit 4

Lesson 3

Objectives

• Understand that certain drugs interfere selectively with neurotransmission

• Realize the effect of a drug is dependent upon dosage and route of administration

Drugs of Abuse

• Useful for investigating brain functions

– Can mimic actions of neurotransmitters

– Can block actions of neurotransmitters

– Apply effects on homeostasis

– Apply effects on behavior

Drugs Disrupt Neurotransmission

• Produce feelings of pleasure by altering neurotransmission by neurons in the Reward system that release the neurotransmitter - DOPAMINE

Methamphetamine

• Causes a release of dopamine

Nicotine

• Increase the number of action potentials and number of vesicles released from neuron

• Increases dopamine released

Caffeine

• Prevents neurotransmitter-adenosine from binding with its receptor

• Binding Adenosine = sedation

Cocaine

• Blocks dopamine transporter which then increases a rapid rise in dopamine

• Causing a feeling of euphoria

• How Cocaine Alter Neurotransmission Video

Alcohol

• Alters brain neurons

• Binds directly to receptors for acetylcholine, serotonin, and GABA

• Reduces glutamate excitatory effect

• Increases release of dopamine

Factors that Determine How A Drug Affects an Individual

• Environmental

– Stress

– Trauma

– Dosage

– Route of administration

• Biological

– Genetics

The Dose Changes the Drug’s Effects

Drugs Enter the Brain in Different Ways

• Routes of administration

– Injection

– Inhalation

– Snorting/snuffing

– Ingesting

– Through the skin

Effects of Methamphetamine

Activity: Drugs Alter Neurotransmission

Activity: How Does Caffeine Affect You?

REMINDERS:

Stay in your seat during the activity

You can read or talk quietly with your group but stay still

Activity: Routes of Administration