Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Block 3 Week 1 > Sanders Enteric Nervous System > Flashcards

Sanders Enteric Nervous System Flashcards

1
Q

What are the 2 components of the enteric nervous system and what are they controlled by?

A

myenteric-> parasympathetics (motility)

submucousal->sympathetics (BV)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

The gut has the ability of (blank) motor and secretory activity (i.e it could be transplanted and work fine)

A

INTRINISIC

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are the sensory neurons of the enteric?

A

chemoreceptors
mechanoreceptors
thermoreceptors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are the interneurons of the enteric?

A

reflex circuits and motor neurons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are the motor neurons of the enteric?

A

excitatory and inhibitory

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are the effectors of the enteric?

A

epithelium (mucosa)
muscles
BVs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

(blank) are the final common pathway controlling the motility of the GI tract

A

motor neurons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

motor neurons on largely located in the (blank) and the outer (blank) close to circular muscle layer

A

myenteric plexus

submucous plexus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Explain the layers of the small intestine from the mucosa inwards

A

mucosa, submucosa w/ BVs, submucous plexus circular muscle, myenteric plexus, longitudinal muscle, mesentary

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

The mesenteric membrane has what 2 things

A

BVs and extrinsic nerves

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is in between the longitudinal and circular muscle?

A

myenteric plexus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Within the circular muscle layer is the non-ganglionated (blank) which contains the axons of motor neurons

A

deep muscular plexus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

THe (blank) is split into layers that giverise to the mucosal plexus on the back of the mucosa.

A

submucous plexus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

(blank) cells transduce luminal mechanical and/or chemical stimuli into the release of signaling molecules including peptides and amines. There are at least 14 different populations of these cells scattered throughout GI epithelia

A

enteroendocrine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

(blank), which contain and secrete serotonin (5-HT), are the largest population of enteroendocrine cells and have the most widespread distribution. These cells have both chemosensitive and mechanosensitive capabilities

A

enterchromaffin cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

(blank) cells are the primary sensory organ affecting GI motility.

A

enterchromaffin cells (EC)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

(blank) cells contain 90% of the body’s 5-HT.They respond to mechanical stimulation and luminal chemicals including bacterial toxins.

A

Enterochromaffin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

5-HT released from these cells activates (blank) which trigger the emetic response, secretion and diarrhoea to expel potentially harmful substances from the body.

A

vagal afferents

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Once 5-HT is released, how do you get rid of it?

A

with SERT (seritonin reuptake transporter) or put into the blood to be placed in platelets for later use

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Following inflammation what happens to EC cells and SERT?

A

EC cells increase and SERT decreases which may explain IBS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What does TPH1 (tryptophan hydroxylase) do?

A

converts tryptophan into seritonin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What does L-AADC (aromatic L amino acid decarboxylase)

A

converts 5HTP to 5HT

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

At rest, 5‑HT is synthesized by enterochromaffin cells. Upon mechanical or chemical stimulation,what happens?

A

5‑HT is released into the interstitial space of the lamina propria and binds to receptors on nearby nerve fibers

24
Q

5‑HT signalling is terminated during the recovery phase: 5‑HT is transported by (blank) into epithelial cells where it is enzymatically degraded, or it enters the (blank) where it is transported into platelets and stored for future use.

A

SERT

blood stream

25
Q

Most of the intrinsic and extrinsic primary afferent neurons that innervate the gut extend processes into the (blank) of the mucosal layer where they can become exposed to 5‑HT released by enterochromaffin cells.

A

lamina propria

26
Q

Where do you homeostatic and digestion reflexes come from?

A

vagal affarents

27
Q

Were do your pain and discomfort reflexes come from?

A

spinal affarents

28
Q

Intrinsic and extrinsic affarent neurons that extend into the LP of the mucosal layer include (blank) afferent fibres arising from the nodose ganglion, spinal afferent fibres arising from (blank) ganglia, and intrinsic (blank) neurons located in submucosal and myenteric ganglia. There is also a class of mechanosensitive (blank) neurons in the myenteric ganglia that do not project to the mucosal layer.

A

vagal
dorsal root
AH
S

29
Q

What are the 5 ways to classify enteric neurons?

A 
morphological
electrophysiological
neurochemical
pharmacological
retrogade labelling
30
Q

What did FITC show us?

What did Calretinin show us?

A

NO synthase in inhibitory motor neurons

Longitudinal muscle motor neurons

31
Q

One of the major excitatory transmitters of enteric neurons is (blank). Neurons that synthesize acetylcholine contain the enzyme (blank).

A 
acetylcholine
choline acetyltransferase (ChAT)
32
Q

(blank) have large smooth cell bodies, are multipolar, have filamentous dendrites and are intrinsic afferent neurons. 20-30% of all enteric neurons are this.

A

AH neurons or Type II neurons

33
Q

By looking at an action potential, how can you tell you are dealing with an AH cell?

A

You will see either 1 or 2 spikes followed by a long-lasting hyperpolarizing after-potential. Even increasing the injected current does not alter this response. ie. spike then latency

34
Q

What type of cells are AH/type II neurons?

A

intrinsic primary afferent neurons (IPANs)

35
Q

Explain what causes the action potential and latent period of an AH cell

A

Ca channels open and cell depolarizes=AP
Ca activate K+ channels are opened and potassium moves down gradient out of neuron=repolarization
continually movement of K+ out=hyperpolarization
After hyperpolarization finally ends after Ca is pushed out of cell or sequestered into intracellular stores

36
Q

Generation of excitatory post-synaptic potentials (EPSPs) in AH neurons causes them to become more (blank).

A

excitable

37
Q

(blank) controls peristaltic propulsion of luminal contents. This neural control requires gating mechanisms to determine distance and direction of propagaion.

A

neural regulation

38
Q

(blank) increase gating of sensory inputs to enhance responses.

A

Excitatory post-synaptic potentials (EPSPs)

39
Q

AH neurons synapse with each other and other (blank) neurons by releasing (blank) forming a self-reinforcing network.

A

S neurons

tachykinins

40
Q

AH neurons communicate with each other and other S neurons via (blank ). Because of these synaptic interactions, mucosal stimulation of one AH neuron could lead to the excitation of other AH neurons. In this way, the activity of AH neurons in a region of intestine is coordinated, potentially leading to synchronous activation of many neurons in response to stimulation.

A

slow excitatory postsynaptic potentials (SEPSPs

41
Q

The sensory info in the gut is very distributed (due to connecting neurons) to produce a (blank) , this is why it is difficult to pin point where your pain in your gut stems from.

A

field effect

42
Q

Networks of interconnected intrinsic sensory neurons (IPANs) or (blank) cells detect mechanical distortion and lumenal chemistry. These synapse with descending and ascending (blank), (blank) and (blank)

A

AH
interneurons
excitatory muscle neurons
inhibitory muscle neurons

43
Q

(blank) neurons have rough cell bodies with short lamellar dendrites, with a single long axon and are motor and interneurons.

A

Type 1 neurons/ S neurons

44
Q

How can you tell you are dealing with an S neuron by looking at an action potential induced by a current?

A

S neuons fire action potentials throughout the duration of a depolarization current. They frequency of the repetitive spikes discharge in proportion to the amplitude of the injected current.

45
Q

(blank) typically have very fast action potentials, whereas those of (blank) are distinguished by an inflection or “hump” on their falling phase, which tends to prolong the duration and which has been shown to be due to influx of Ca2+ ions. This then triggers after-hyperpolarisation via calcium-activated potassium channels

A

S cells

AH cells

46
Q

Which have longer action potential, AH or S cells?
Which have steeper APs?
Which have more frequent APs?

A

AH
AH
S

47
Q

S cells/ Type I neurons (which contain VIP or NO) in the myenteric plexus send projections in an aboral direction, traveling for only a few millimeters before entering the circular muscle layer. These neurons are considered (blank)

A

inhibitory motor neurons

48
Q

Dogiel type I neurons (which contain ACh or Substance P) in the myenteric plexus send projections in an oral direction, traveling for only a few millimeters before entering the circular muscle layer. These neurons are (blank) motor neurons that lead to contraction of the circular layer.

A

excitatory

49
Q

Dogiel type I neurons in the submucosal plexus containing VIP are excitatory motor neurons to the intestinal crypts and are called (blank) , they stimulate the crypts to secrete water, electrolytes and mucus

A

secretomotor neurons

50
Q

If you have type 1 cells sending projections in the oral direction what are they?
If you have type 1 cells sending projections in the aboral direction then what are they?

A

excitatory

inhibitory

51
Q

If you have type 1 neurons in the submucosal plexus what are they?

A

excitatory secretomotor neurons

52
Q

The main motor output that the myenteric plexus produces is (blank)

A

peristaltic reflex

53
Q

Neurons above the site of stimulation are (blank) , below the site of stimulation are (blank) (hyperpolarization).

A

excitatory

inhibitory

54
Q

Neurons above the site of stimulation are excitatory, below the site of stimulation are inhibitory (hyperpolarization). This is called the (blank) reflex

A

receptive reflex

55
Q

(blank) occurs after the stimulus has been turned off, there is an excitatory effect that helps give an extra push.

A

Rebound excitation

56
Q

Explain the pathway before the stimulus:

A

stimulus is transduced by enterchromaffin cells which stimulate affarents which stimulate ascending interneurons which stimulate excitatory motor neurons which stimulate contraction via AcH or neurokinins

57
Q

Explain the pathway after the stimulus

A

stimulus-> EC cells-> intrinsic primary affarent-> descending interneuron-> inhibitory motor neuron->relax

Block 3 Week 1 (18 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions