10 Adrenergics I Flashcards Preview

1 Pharm Unit > 10 Adrenergics I > Flashcards

Flashcards in 10 Adrenergics I Deck (82)
Loading flashcards...
1
Q

10 adrenergics I

which receptor when stimulated supplies parasympathetic activity to the heart?

A

M2 receptor.

2
Q

10 adrenergics I

Most organs/structures are innervated heavily by both the sympathetic and parasympathetic divisions. Which structures are solely sympathetic innervation?

A

1) blood vessels
2) sweat glands
3) liver
4) spleen
5) adrenal glands

3
Q

10 adrenergics I

where (generally) are adrenergic receptors found?

A

1) presynaptically (on postganglionic nerve terminals)

2) Postsynaptically (on target tissues)

4
Q

10 adrenergics I

which 2 adrenergic receptors are found on the nerve terminals of postganglionic nerves?

A

Alpha 2DA 2

5
Q

10 adrenergics I

T/F You find the Alpha 1, Beta 1, Beta 2, and DA 1 receptors on target tissues only?

A

True

6
Q

10 adrenergics I

What are the three catecholamines that are naturally occurring within the nervous system and clinically useful?

A

1) Norepinephrine
2) Epinephrine
3) Dopamine

7
Q

10 adrenergics I

what is considered the primary NT of adrenergic nerves?

A

Norepinepherine

8
Q

10 adrenergics I

Where does the major source of epi come from?

A

adrenal medulla

9
Q

10 adrenergics I

Where is dopamine released in the PNS?

A

By postganglionic sympathetic nerves of the renal and splanchnic vascular smooth muscle.

10
Q

10 adrenergics I

How is epinephrine made?

A

1) Tyrosine (tyrosine hydroxylase)
2) DOPA
3) Dopamine
4) Norepinephrine
5) Epinephrine

11
Q

10 adrenergics I

What controls the rate of epinephrine formation?

A

The rate of neuronal firing.

12
Q

10 adrenergics I

What is the rate limiting step in epinephrine synthesis?

A

Tyrosine to DOPA through tyrosine hydroxylase because it is controlled by negative feedback.

13
Q

10 adrenergics I

What is COMT? Where is it found? What does it do?

A

COMT= Catechol o methyltransferase.It is found mainly in the liver.It methylates catecholamines rendering them inactive.

14
Q

10 adrenergics I

what is MAO? Where is it found? what does it do?

A

1) MAO= Monoamine oxidase
2) found mainly in the liver, adrenergic nerve terminals, and brain.
3) Deaminates catecholamines.

15
Q

10 adrenergics I

Isoproterenol, dobutamine, and terbutaline are all adrenergic receptor agonists that have large alkyl moieties. What does the large alkyl moiety do for the drug?

A

It increases Beta activity. (note: the alkyl group is the very end ‘R’ group)

16
Q

10 adrenergics I

T/F Catecholamines have an OH at the 3/4 postition?

A

true

17
Q

10 adrenergics I

What happens when you loose the hydroxyl group on the catecholamine?

A

1) Decreased potency

2) increased duration of action because COMT cant metabolize it easily.

18
Q

10 adrenergics I

Metaraminol, phenylephrine, and ephedrine all act as long lasting adrenergic agonist because?

A

These drugs all have a substitution to the benzene ring such as the loss of a hydroxyl.

19
Q

10 adrenergics I

what happens when you form a drug (catecholamine agonist) that has a substitution on the alpha carbon?

A

You end up getting a long lasting catecholamine type reaction because MAO is not able act on the molecule easily.

20
Q

10 adrenergics I

Metaraminol and ephedrine can have substitutions to the benzene ring to extend their half lives. What else can these two drugs do to extend their lives?

A

Have a substitution on the alpha carbon. They have this substitution to help slow/prevent the breakdown from MAO.

21
Q

10 adrenergics I

Agonists for the alpha 1 adrenergic receptor have what function? What is the exception?

A

1) In general, contraction and constriction of smooth muscle. 2) It causes relaxation of intestinal smooth muscle

22
Q

10 adrenergics I

An agonist of the alpha 2 receptor would act where?

A

1) postganglionic sympathetic nerve terminals

23
Q

10 adrenergics I

What happens when the presynaptic nerve terminal is stimulated at the alpha 2 receptor?

A

negative feedback will inhibit the release of more NE from the postganglionic neuron.

24
Q

10 adrenergics I

phenylephrine, methoxamine, clonidine, and methyl-NE are all drugs that do what?

A

selective agonists for alpha adrenergic receptor (Note they can also activate beta but its much much less)

25
Q

10 adrenergics I

Norepinephrine activates both alpha receptors equally. However, beta receptors are different. Which beta receptor is favored by NE?

A

NE favors Beta 1&raquo_space;Beta 2

26
Q

10 adrenergics I

T/F Epinepherine favors Beta 2 over Beta 1?

A

False.
Beta 1=Beta 2
Also, Alpha 1=Alpha 2

27
Q

10 adrenergics I

Dobutamine, isoproterenol, albuterol, terbutaline, and metaproterenol are what type of drugs?

A

They are Beta agonists.

28
Q

10 adrenergics I

Where do you find Beta 1 receptors (Mainly)?

A

heart and adipose tissue

29
Q

10 adrenergics I

stimulation of Beta 1 receptors leads to?

A
increased:
heart rate
contractility
C.O.
lipolysis
30
Q

10 adrenergics I

What effects will you see with activation of the beta 2 receptor?

A

1) vasodilation in skeletal muscle
2) relaxation of smooth muscle
3) decreased intraocular pressure

31
Q

10 adrenergics I

what does the beta 3 receptor do?

A

Increases glycogenolysis in the liver and skeletal M.

32
Q

10 adrenergics I

Activation of the dopamine (D1 receptor) causes what? Where?

A

1) vasodilation

2) kidney and mesenteric

33
Q

10 adrenergics I

Where do you find the D2 receptor? What do they do?

A

1) Presynaptic nerve terminal

2) The D2 receptor acts as a negative feedback loop to prevent too much NE from being released.

34
Q

10 adrenergics I

Fenoldopam is a drug that does what?

A

Dopamine agonist. D1»D2

35
Q

10 adrenergics I

What is NET?

A

AKA Amine 1 transport. Its a NE reuptake system located on the postganglionic nerve terminal.

36
Q

10 adrenergics I

what percent of NE is recycled back into the postganglionic nerve terminal? What about the rest of the NE?

A

50%The rest of the NE is degraded by MAO and COMT

37
Q

10 adrenergics I

What is the target of cocaine and tricyclic antidepressants?

A

They inhibit the function of Amine 1 transport

38
Q

10 adrenergics I

T/F vasoconstriction, tachycardia, and mydriasis are 3 symptoms associated with cocaine use. Why does this occur?

A

Cocaine block amine 1 transport (NET) and therefore causes further activation of the sympathetic nervous system.

39
Q

10 adrenergics I

What is DMI?

A

DMI=Desmethylimipramine

A tricyclic antidepressant that blocks NET.

40
Q

10 adrenergics I

what effects will you see with and alpha 2 and DA 2 antagonist?

A

Increased sympathetic activation. This is because the release of NE from the postganglionic synapse is not allowing for negative feedback.

41
Q

10 adrenergics I

T/F For Alpha 2 receptors, clinically relevant drugs are lacking?

A

True

42
Q

10 adrenergics I

T/F Antiphychotic drugs such as haloperidol and chlorpromazine act as antagonists to the D2 receptors and also elicit peripheral side effects?

A

True

43
Q

10 adrenergics I

NE is taken back into the synaptic terminal by NET (amine 1 transport). What other drugs/chemical does NET transport back into the nerve terminal?

A

dopamine
tyramine
ephedrine
amphetamine

44
Q

10 adrenergics I

Domamine, tyramine, ephedrine, and amphetamines all increase sympathetic responses. How do they do this?

A

They are all taken up through NET, and once inside the nerve terminal, they displace NE from storage vesicles causing NE to be released into the synapse.

45
Q

10 adrenergics I

Where can you get exogenous tyramine? When does this present as a problem?

A

1) cheeses, sausage, smoked products.

2) This only becomes an issue if you have problems with MAO.

46
Q

10 adrenergics I

How do amphetamines work?

A

They stimulate alpha 1 and beta 1 receptors, act as a NE releasing factor, and are vasopressors.

47
Q

10 adrenergics I

How does ephedrine act on the body?

A

It directly stimulates alpha 1 and beta 1 receptors, and acts as a releasing factor for NE.(Note: mild Beta 2 can occur=dilate bronchial/nasal decongestant)

48
Q

10 adrenergics I

where are alpha 1 receptors found?

A

most smooth muscle and elicit constriction/contraction(Exception: Inhibits the GI smooth muscle)

49
Q

10 adrenergics I

Where are beta 1 receptors found?

A
heart (increase)
adipose tissue (Lipolysis)
50
Q

10 adrenergics I

where are beta 2 receptors found? what do they do?

A

1) bronchioles, intestines, uterus, arterioles of heart and skeletal muscle.
2) They all promote relaxation of smooth muscle. Ex: vasodilation.

51
Q

10 adrenergics I

What happens when you activate a DA 1 receptor?

A

You get increased blood flow to kidney and mesentary because of vasodilation to these structures.

52
Q

10 adrenergics I

T/F Beta 1 and beta 2 receptors are 10x more sensitive to Epi than are alpha 1 and alpha 2 receptors?

A

True

53
Q

10 adrenergics I

Epi stimulates which receptors?

A

all alpha, all beta (beta mainly)

54
Q

10 adrenergics I

NE stimulates which receptors?

A

all alpha, Beta 1 only.

55
Q

10 adrenergics I

Dopamine stimulates which receptors?

A

all dopamine, alpha 1, beta 1

56
Q

10 adrenergics I

Only 50% of the NE is recycled back into the nerve terminal. How does the nerve make up for the lost NE?

A

It transports tyrosine into the nerve terminal and converts tyrosine into DOPA–> dopamine–> NE

57
Q

10 adrenergics I

How does NE get into the vesicle ready to be released?

A

VMAT (vesicular monoamine transporter)

58
Q

10 adrenergics I

What triggers NE release?

A

Ca+ influx derived from an action potential.

59
Q

10 adrenergics I

Upon excitation of the adrenal medulla from the sympathetic nervous system, what is released?

A

80% Epi

20% NE

60
Q

10 adrenergics I

what is pheochromocytoma?

A

A tumor of the adrenal gland that secretes a bunch of Epi and NE into the body. This causes an overwhelming sympathetic response.

61
Q

10 adrenergics I

Will you get excessive sweating with a pheochromocytoma?

A

Yes but only non thermoregulatory apocrine sweat glands will be stimulated.

62
Q

10 adrenergics I

Dopamine in the PNS is mainly secreted for what?

A

Activation of the DA 1 receptor in renal and splanchnic vasculature. (At high doses it can also stimulate alpha 1 and beta 1 receptors)

63
Q

10 adrenergics I

Why is dopamine used for shock?

A

increased vasoconstriction (alpha 1)
increased HR/contractability (Beta 1)
increased blood flow (DA 1)

64
Q

10 adrenergics I

Norepinephrine has its major effects on which receptors?

A

all alpha, beta 1 (It has little to no effect of beta 2)

65
Q

10 adrenergics I

what is Isoproterenol?

A

a very potent beta agonist. (very little alpha activity)

1) increased C.O. with beta 1
2) decreased M.A.P. with beta 2

66
Q

10 adrenergics I

what is considered the most potent vasopressor?

A

Epi because it has both full alpha and beta activity.

67
Q

10 adrenergics I

what is a vasopressor?

A

a vasoconstrictor

68
Q

10 adrenergics I

what happens when you give epi in low doses? high dose? bolus?

A

1) low dose (beta 1 and beta 2 dominate)
2) high dose (beta1, beta 2 and alpha 1 dominate)
3) bollus (Drop in MAP because due to vasovagal response)

69
Q

10 adrenergics I

what do you generally see with infusion of NE?

A

NE infusion increased MAP and decreases HR.

MAP increases because NE lacks Beta 2 receptor activity which would cause vasodilation( smooth muscle relaxation).

70
Q

10 adrenergics I

which 3 drugs are used to overcome hypotensive crisis?

A

NE, Phenylephrine, methoxamine

71
Q

10 adrenergics I

which 2 drugs are used to overcome chronic orthostatic hypotension?

A

midodrine, ephedrine

72
Q

10 adrenergics I

which 1 drug is great for treating shock and why?

A

Dopamine. alpha 1, beta 1, and DA 1 activity.

73
Q

10 adrenergics I

which 2 drugs are great at slowing/stopping blood flow during surgery?

A

epinephrine, cocaine

74
Q

10 adrenergics I

which 3 drugs are useful to help prevent diffusion of local anesthetics?

A

Epi, NE, phenylephrine

75
Q

10 adrenergics I

which 3 drugs help with reducing congestion of mucous membranes?

A

phenylephrine, ephedrine, pseudoephrine

76
Q

10 adrenergics I

which 1 drug is useful for rescuing cardiac function during a heart block of cardiac arrest?

A

epinephrine

77
Q

10 adrenergics I

which 1 drug is useful for rescuing cardiac function during heart failure?

A

dobutamine

78
Q

10 adrenergics I

metaproterenol, terbutaline, and albuterol are all beta 2 selective drugs designed to treat what?

A

bronchial asthma.

79
Q

10 adrenergics I

what is anaphylaxis and how do you treat it?

A

1) bronchospasm
2) mucous membrane congestion
3) angioedema
4) hypotension(treated with epi)

80
Q

10 adrenergics I

which type of drug is used to treat glaucoma?

A

Beta antagonists generally.

81
Q

10 adrenergics I

terbutaline does what for the pregant woman?

A

relax pregnant uterus

82
Q

10 adrenergics I

ephedrine is used in the genitourinay tract to do what?

A

correct stress incontinence.