Brainscape's Knowledge GenomeTM

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


See full index

Sp. Phys 1 > 4b. Smooth Muscle > Flashcards

4b. Smooth Muscle Flashcards

1
Q

Smooth muscle

A

autonomic nervous system

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

smooth muscle located

A

vasculature
airways
gut

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

blood vessel outside

A

smooth muscle

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

blood vessel inside

A

endothelial cells

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

multi-unit

A

each cell is innervated separately
so each behaves independently
not coordinated

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

single-unit

A

innervated in series
gap junctions permit coordinated contraction
spontaneous action potential

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

single unit smooth muscles

A

walls of hollow organs
airways
uterus
visceral smooth muscle

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

multi-unit smooth muscles

A

airways
larger arteries
ciliary muscle of eye

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

smooth muscle structure

A

smaller than skeletal
single nucleated
no striations
actin and myosin

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

smooth muscle contraction speed

A

slower
duration longer

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

3 types of muscle cells

A

skeletal - voluntary
cardiac - involuntary
smooth - involuntary

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

smooth muscle membrane potential

A

-50 to -60 mV

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

smooth muscle depolarization rising phase

A

VG Ca++ channels
+ some Leak Ca++ channels

some smooth muscle can contract w/graded potential

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

Ca++ pathways into cell in smooth muscle contraction

A
  1. VG Ca++ channel
  2. stretch-activated Ca++ channel
  3. NT/hormones Gprotein complex
  4. CICR
  5. SOCE
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How does the G-protein complex induce Ca++ release into Cytosol?

A

G protein complex stimulates Phospholipase C to release IP3

IP3 binds to SR Ca++ channels
Ca++ released from SR into cytosol

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

how does CICR release Ca++ into cytosol?

A

Ca++ from cytosol binds to the CICR
CIRC pumped from SR to cytosol

(positive feedback)

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

how does Store operated calcium entry (SOCE) work?

A

SR Ca++ stores become depleted
signal triggers SO Ca++ channel to open
Ca++ flows into Cytosol

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

smooth muscle contraction

A
  1. increase intracellular Ca++
  2. Ca++ binds to calmodulin (CaM)
  3. Ca++/CaM activates Myosin Light Chain Kinase (MLCK)
  4. MLCK phosphorylates light chain in myosin heads (incr ATPase activity)
  5. cross bridge cycling creates muscle tension
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

what inhibits MLCK?

A

cAMP

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

conformation change

A

1) increases ATP activity
2) allows myosin/actin interaction

21
Q

increase cAMP

A

inhibits MLCK
muscles cannot contract

22
Q

smooth muscle relaxation

A

decrease intracellular Ca++
increase MLCP activity

23
Q

MLCP

A

myosin light chain phosphatase

24
Q

how do you activate MLCP?

A

cGMP

25
Q

Nitric Oxide (NO)

A

released by endothelium
causes smooth muscle relaxation
vasodilator

26
Q

first signs of vascular disease

A

decrease in NO

27
Q

how does NO cause smooth muscle relaxation?

A

NO released by endothelium
NO stimulates guanylyl cyclase
GTP convert to cGMP
increased cGMP causes relaxation of smooth muscles

28
Q

cGMP

A

inhibits Ca++ entry
activates MLCP

29
Q

adrenergic receptors

A

alpha 1
alpha 2
beta 1
beta 2

30
Q

cholinergic receptors

A

muscarinic : M1-M5
nicotinic: N1-N2

31
Q

blood vessels receptors

A

most blood vessels have only adrenergic receptors

some have bothh cholinergic and adrenergic

32
Q

adrenergic receptors cause

A

mostly vasoconstrictions
some vasodilations

33
Q

cholinergic receptors cause

A

only vasodilations

34
Q

vascular smooth muscle (BV)
alpha 1

A

NE binds to alpha 1
G-protein complex
Phospholipase C produces IP3
IP3 binds to Ca++
Ca++ released into cytosol
increase Ca++
smooth muscle contraction
(vasoconstriction)

35
Q

vascular smooth muscle (BV)
beta 2

A

NE or Epi binds to Beta 2
increase cAMP
inhibits MLCK
smooth muscle contraction
(Vasodilation)

36
Q

B2 receptors in BV location

A

BV that support organ/tissue:
coronary
skeletal muscle
pulmonary

37
Q

BV mainly innervated by

A

sympathetic nerves

38
Q

some BV innervated by

A

parasympathetic nerves

39
Q

Parasympathetic effects on vasculature

A

Ach releases NO from endothelium
NO is vasodilator

40
Q

if you have a damaged endothelium

A

less NO would be released?

41
Q

Sympathetic effects on smooth muscles in bornchioles

A

Epi>NE
NE or Epi binds to beta 2
cAMP increased
inhibits intracellular Ca++ release
decrease Ca++
decrease smooth muscle contraction
(bronchodilation)

42
Q

parasympathetic effects on smooth muscles in bronchioles

A

Ach binds to muscarinic receptor
G protein complex
phospholipase C releases IP3
increases cytosol Ca++
increase smooth muscle contraction
(bronchoconstriction)

43
Q

bronchodilation receptor

A

Beta 2

44
Q

bronchoconstriction receptor

A

M3

45
Q

Paracrine factors in smooth muscle vasodilation

A

High CO2
High H+
NO

46
Q

paracrine factors in smooth muscle vasoconstriction

A

Low O2
(hypoxic pulmonary vasoconstriction)

47
Q

endocrine vasoconstrictors

A

angiotensin II
endothelin
vasporessin
serotonin

48
Q

endocrine vasodilators

A

histamine

49
Q

Stretch (in gut)…

A

increases contraction

Sp. Phys 1 (6 decks)

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