NEURO LEC 2: SYNAPSES

Question 1

What are the 3 parts of a synapse?

Answer 1

Pre-synaptic terminal

Synaptic Cleft

Post-synaptic terminal

Question 2

If a synapse is ______, the presynaptic effect occurs

Answer 2

axoaxonic

Question 3

a strong excitatory stimulus in the presynaptic terminal leads to ____________.

more ________ leads to larger amount of neuro transmitter released

Answer 3

More action potentials

action potentials

Question 4

IPSP means what?

Answer 4

Inhibitory post synaptic potential

Local hyperpolarization that occurs with the influx of **Cl- or K+ OUT of neuron **

Remember: Na Ca (NASA) flows in (during EPSP), whereas CL K clocks out! (During IPSP)

Question 5

Summation of (EPSP OR IPSP) determines whether or not an action potential is generated?

Answer 5

EPSP

Question 6

What is pre synaptic facilitation

Answer 6

When the 1st presynaptic neuron causes slight local depolarization of a 2nd neurons presynaptic terminal

When an AP arrives, the duration is increased allowing for more CA2+ influx

Question 7

What is presynaptic inhibition

Answer 7

1st presynaptic neuron causes a 2nd to have local hyperpolarization

therefore when an AP arrives, the duration is decreased allowing less CA2+ influx

Question 8

What has a longer duration, Neurotransmitters or neuromodulators

Answer 8

Neuromodulators.

Neuromodulators last for **mins to days **whereas neurotransmitters last for milliseconds to Mins

Question 9

Which of the following use EPSP and IPSP as their method of action.

Neuromodulator or Neurotransmitter

Answer 9

Neurotransmitter

Question 10

What is the method of action of neuromodulators?

Answer 10

Alter gene expression

open ion channels

change metabolism

affects many neurons

Question 11

Neurotransmitters act in the synapse whereas neuromodulators act in the ___________

Answer 11

Extra cellular space

Question 12

Neuro messengers can function as a neuromodulator or neurotransmiter depending on…

Answer 12

If they’re released in the synapse or the extracellular space

Question 13

The effect of a neurotransmitter is related to

A. Type of receptor

or

B. Type of chemical that the neurotransmitter is

Answer 13

A. type of receptor

Some neurotransmittors can be excitatory in some places and inhibitory in other places

Question 14

At rest, ligand gated ion channels are _____

Answer 14

Closed

Question 15

What is a G-Protein?

Answer 15

Guanine Nucleotide binding protein

A protein that alters the electrical excitability of neurons, can activate ion channels

Question 16

What is faster, a G protein activated channel or a Ligand gated ion channel

Answer 16

Ligand gated

Question 17

Drug that binds to receptor and copies the action of neurotransmitters

Answer 17

Agonist

Question 18

Acetylcholine, Glutamate, and GABA are all….

Answer 18

Amino Acids

Question 19

Dopamine, Norepinephrine, and seratonin are all considered…

Answer 19

Amine

Question 20

Substance P is considered a…

Answer 20

Peptide

Question 21

Where is acetylcholine produced

Answer 21

produced in Basal forebrain and midbrain

Question 22

All neurons that synapse with skeletal muscles use _____ to elicit a fast acting effect on muscle membranes. It’s an excitatory neurotransmitter found in muscle junctions

Answer 22

Acetylcholine (Ach)

Question 23

Blocking ____ receptors causes weakness, fatigue, and paralysis

Answer 23

Acetylcholine

Question 24

Acetylcholine effects the Autonomic nervous system by

Answer 24

Slowing HR

Constricting Pupils

and Increases smooth muscle contractions/ digestion

Question 25

Acetylcholine effects the brain by

Answer 25

Stimulating arousal, pleasure, and cognitive function Acts as a slow neuromodulator in control of movement and attention

Question 26

______ is the principal fast excitatory neurotransmitter of the CNS in virtually every brain region and related to neural changes with learning and development

Answer 26

Glutamate “Glutamate is the most exciting and that’s why he’s our mate”

Question 27

Glutamate levels must be closely regulated, excess levels can lead to

Answer 27

Excitotoxicity/neuron death epileptic seizures

Question 28

______ is the primary inhibitory neurotransmitter in the CNS. Especially with interneurons in the spinal cord

Answer 28

GABA

Question 29

Alcohol, barbiturate, anticonvulsants, and baclofen mimic what neurotransmitter

Answer 29

GABA (Inhibitor to CNS)

Question 30

______ inhibits postsynaptic membranes mostly in the brainstem and spinal cord

Answer 30

Glycine

Question 31

Huntington's disease causes loss of neurons in the striatum that use _____ with jerky and involuntary movements and cognitive decline

Answer 31

GABA

Question 32

Dopamine is produced in the _____ of the brain

Answer 32

Substantia Nigra of brain

Question 33

All receptors of dopamine are _______

Answer 33

Secondary messengers

Question 34

What disease is associated with a lack of dopamine?

Answer 34

Parkinson's disease

Question 35

Secondary messenger systems are typically (faster or slower)

Answer 35

Slower

Question 36

Excessive ______ levels are seen in cocaine or amphetamine abuse by preventing reuptake by presynaptic terminals

Answer 36

dopamine

Question 37

Where is norepinephrine produced?

Answer 37

Brainstem, hypothalamus, and thalamus

Question 38

What neurotransmitter is released by neurons of the autonomic nervous system and secreted by adrenal glands, which is responsible for "fight or flight"

Answer 38

Norepinephrine

Question 39

Excessive ______ is found in people with PTSD

Answer 39

Norepinephrine

Question 40

______ is involved in mood, pain perception, arousal, and motor activity Low levels seen in depression Lowest during REM sleep

Answer 40

Seratonin

Question 41

_______ stimulates nerve endings at injury sites acts as a neurotransmitter carrying CNS information from spinal cord to brain

Answer 41

Substance P

Question 42

What neurotransmitter can also act as a neuromodulator in pain syndromes, and modulates immune system during times of high stress

Answer 42

Substance P

Question 43

Lambert Eaton syndrome is....

Answer 43

Antibody damage to volatage gated **Ca2+** in **presynaptic terminal** of neuromuscular junction -Decreased release of neurotransmitters -decreased muscle excitation -muscle weakness How i will remember: Lambert Eaton needs to eat more calcium because his muscles are weak”

Question 44

Myasthenia Gravis is...

Answer 44

Antibodies (autoimmue) cause damage to AcH receptors on muscle cells. (You still have plenty of AcH) -Causes fatigue -can be life threatening

Question 45

When a pre-synaptic terminal depolarizes, the voltage gated ____ channels open

Answer 45

Ca+

Question 46

EPSP means what?

Answer 46

Excitatory Post Synaptic Potential -The local **depolarization** that occurs with the flow of **Na+ and Ca2+** into the neurons A summation of EPSP's facilitates Action Potential generation

Question 47

When stimulation duration is _____ in the presynaptic cell, the series of action potentials is longer

Answer 47

longer

Question 48

If a synapse is _____ , _____ or ______ , the ions flow through the ligand-gated channels to cause local membrane potential

Answer 48

Neuromuscular, axosomatic, or axodendritic (not axoaxonic)

Question 49

Define a synapse

Answer 49

Where a neuron transfers information to 1 or more neurons/muscle specialized zone of contact

Question 50

Receptors for opiod peptides are mainly found where?

Answer 50

Spinal cord, hypothalamus, and brainstem in areas that inhibit pain perception

Question 51

What are 2 causes of an increase in the number of receptors for a specific neuro transmitter

Answer 51

Infrequent activation or low levels of neurotransmitter

Question 52

Overstimulation of post synaptic receptors can cause...

Answer 52

A decrease in the number of receptors available

Question 53

What are two ways that the body restricts the number of receptors available

Answer 53

Inactivate receptors or Internalize receptors into cell body

Question 54

What is the 1st and 2nd messenger in the G-Protein second messenger system

Answer 54

1st- Neuromodulator 2nd- Chemical produced inside neuron

Question 55

What are the 3 steps of a G protein activation of ion channels

Answer 55

1. Receptor Protein alters shape and internal G protein is triggered 2. G protein subunits break away and bind to ion channels 3. Ion channels open

Question 56

Myasthenia graves destroys what receptors

Answer 56

L Ach