Tipsy Neurons

Jackie BarlowJoseph EsdinTrish Hartzell

Kalyani MaitraMiriam Martin

Xia Yang&

Jim Burnette

NASI TidbitEducational context

1. sophomores biology majors in a physiology coursemid-semester

2. students have knowledge of Basic chemistry, biologyBasic molecular interactionsEnzyme-substrate

3. students will be expected to have read background information about neurons, synapses, neurotransmitters

Kalyani

Goals/Objectives:

After this class, students will understand…

1. How signals are transmitted by neuronsInhibitoryExcitatory

2. Molecular mechanism of chemical perturbation of neuron function

The story continues (next lecture) with signal transduction.

Kalyani

Learning OutcomesBy the end of the lesson, students will be able to:

-Draw the sequence of events during neuronal transmission

-Compare and contrast inhibitory and excitatory synapses

-Predict how receptor agonists and antagonists might interfere with neuron signal transmission

Kalyani

AssessmentFormative• Draw the sequence of events during neuron transmission• Predict – how receptor agonists and antagonists might interfere with

neuron signal transmission– the cumulative effect of multiple ligands for neuron receptors

Summative• Explain how excitation of an inhibitory pathway can lead

to change of function

Kalyani

Good afternoon

Trish

Trish

Sending messages to the brain

stimulus

output to brain

memory, coordinationbalance, pain, pleasure

Trish

The brain is made of billions of neurons

Joseph

Synapse

Presynaptic neuron

Postsynaptic neuron

Neurons form junctions called synapse and communicate by electrical signals Joseph

Synapse

Presynaptic neuron

Postsynaptic neuron

Neurotransmitter release

Joseph

Neural Transmission

Neurotransmitter

Synaptic cleft

Pre

Post

Joseph

Draw the sequence of events during neuron transmission

Joseph

Physiology of the Synapse

Voltage gated calcium channel

1

2

3

4

Neurotransmitter binding to ligand gated channels (receptors) 6

5 7

7

7

Action potential

Vesicles mobilization

Neurotransmitter release

Changes in the postsynaptic neuron

Breakdown of the neurotransmitter

Joseph

If neurotransmitter is inhibitory!

1

2

3

4

6

5 7

7

7

GABA release

Activity decreases in the postsynaptic neuron

If neurotransmitter is excitatory!

1

2

3

4

6

5 7

7

7

Glutamate release

Activity increases in the postsynaptic neuronJoseph

Xia

What happens after you drink alcohol?

? ?

Xia

Which image represents the effect of alcohol on the balance between inhibition and excitation?

A

B

CXia

Inhibition Excitation

Inhibition

Inhibition

Excitation

Excitation

Alcohol exposure enhances inhibition and decreases excitation

Xia

GABA

Glutamate

Miriam

Activity

GABA

Glutamate

How alcohol enhances inhibitory actions of GABA neurotransmission

Agonist

Jackie

(+)

How alcohol reduces the excitatory actions of glutamate neurotransmission

Alcohol

(-)

Antagonist

Jackie

Summative

Jackie

Alcohol + “downers” = ???

Xanax

Jackie

Thank You!!!