ANS pharmacology 1

Question 1

autonomic nerves innervate

Answer 1

smooth muscle cells, cardiac tissue, exocrine glands

Question 2

somatic nerves innervate

Answer 2

skeletal muscle cells

Question 3

connection between CNS and organ in autonomic

Answer 3

pre and pos ganglionic neurons

Question 4

connection between CNS and organ in somatic

Answer 4

single motor neurone

Question 5

primary role of autonomic nerves

Answer 5

homeostasis
cardiac output
digestion
blood flow

Question 6

primary role of somatic nerves

Answer 6

voluntary control
locomotion
posture
respiration

Question 7

parasympathetic nervous system nerve type

Answer 7

○ Cholinergic nerves

§ Synthesize store and release acetyl choline

Question 8

pre ganglionic receptors in parasympathetic

Answer 8

○ Ach released from pre ganglionic nerve activates nicotinic cholinoceptors on the cell surface of post ganglionic nerves

Question 9

post ganglionic receptors in parasympathetic

Answer 9

○ Ach released from post ganglionic nerves activates muscarinic cholinoceptors on surface of effector cells

Question 10

parasympathetic nerves exist spinal cord at

Answer 10

○ From cranial/sacral nerves

Question 11

sympathetic nerves exist spinal cord at

Answer 11

thoracic or lumbar nerves

Question 12

sympathetic pre gangliomic nerve

Answer 12

• Pre ganglionic nerve is cholinergic

Question 13

sympathetic post ganglionic nerve

Answer 13

• post ganglionic is adrenergic

○ Uses noradrenaline

Question 14

varicosities

Answer 14

(swellings in nerves

○ Contain vesicles of neurotransmitter, which are released by nerve AP

Question 15

• Adrenergic nerves

Answer 15

○ Synthesize store and release NA

○ Most sympathetic post ganglionic nerves

Question 16

• Cholinergic nerves

Answer 16

○ Synthesize store and release Ach
○ All parasympathetic post ganglionic nerves
○ Several sympathetic post ganglionic nerves

Question 17

acetyl choline works on

Answer 17

choliceptors

Question 18

2 types of cholinoceptors

Answer 18

nicotinic and muscarinic

Question 19

3 muscarinic types

Answer 19

M1. M2, M3

Question 20

M2 cholinoceptors

Answer 20

decrease heart rate

Question 21

M3 cholinoceptor

Answer 21

contract smooth muscle and secrete glands

Question 22

2 types adrenoceptors

Answer 22

Alpha beta

a1, a2, B1, B2, B3

Question 23

4 adrenoceptor agonists

Answer 23

adrenaline and noradrenaline and phenylephrine and salbutamol

Question 24

adrenaline

Answer 24

§ Stimulates all adrenoceptor subtypes
§ Inactive orally due to extensive metabolism in the GIT and liver
□ Typically given by injection

Question 25

a1 adrenoceptors

Answer 25

contract vascular smooth muscle

Question 26

b1 adrenoceptors

Answer 26

increase heart rate and force of contractility

Question 27

b2 adrenoceptors

Answer 27

relax smooth muscle

Question 28

adrenaline as local injection

Answer 28

□ High affinity for B2 and lower affinity for a1 low doses binds B2 for vasodilation high dose binds a1 for vasoconstriction

Question 29

adrenaline as slow intravenous

Answer 29

◊ Delivers constant levels of adrenaline over time ◊ Increases heart rate } Stimulates B1 receptors in the heart

Question 30

adrenaline in intravenous infusion effect on blood pressure

Answer 30

} Increase systolic blood pressure – Stimulates B1 and increases force of contraction of cardiac muscle } Decrease in diastolic blood pressure – Because TPR decreases

Question 31

adrenaline in intravenous infusion effect on total peripheral resistance

Answer 31

} A1 mediated vasocontraction } B2 mediated vasodilator effect – Predominantly in vascular beds of skeletal muscle – Overrides A1 mediated vasoconstriction in other vascular beds } Net effect is for TPR to decrease

Question 32

slow bolus adrenaline

Answer 32

□ Initially high levels which decrease as Adr is metabolised

Question 33

slow bolus adrenaline affect on total peripheral resistance

Answer 33

® At high doses ◊ Primarily a1 receptor mediated vasoconstriction ◊ Causes increase is diastolic blood pressure

Question 34

slow bolus adrenaline affect on systolic blood pressure

Answer 34

® Activated B1 adrenoceptors to increase force of contractility ® Increase in mean arterial blood pressure

Question 35

slow bolus adrenaline affect on heart rate

Answer 35

® Vagus nerve mediates decrease in heart rate as a reflex response to increase in blood pressure

Question 36

slow bolus adrenaline as concentration decreases

Answer 36

® Vasodilation effect, decrease in total peripheral resistance, increase in heart rate (direct effect of adrenaline)

Question 37

3 clinical uses of adrenaline

Answer 37

added to local anaesthetic to prolong the action restores cardiac rhymthm in cardiac arrest used in cute anaphylactic shock

Question 38

- Noradrenaline

Answer 38

○ Also inactive orally due to metabolism in the Git and liver ○ Stimulates all AR subtypes except B2 ○ Does not cause vasodilation

Question 39

noradrenaline on heart rate

Answer 39

□ Direct effects of noradrenaline are overridden by vagal cardiac reflexed activated by increase in mean arterial blood pressure

Question 40

noradrenaline effect on blood pressure

Answer 40

□ Increase in diastolic blood pressure □ Increase in systolic blood pressure ® Response to activation of B1 force of contractility

Question 41

noradrenaline effect on total peripheral resistance

Answer 41

Increases due to activation of a1 vasoconstriction in all major vascular beds

Question 42

2 selective adrenoceptor agonsists

Answer 42

phenylephrine and salbutamol - Are not extensively metabolised in the gut and the liver ○ Are active orally

Question 43

- Phenylephrine

Answer 43

○ Activates a1 on vascular smooth muscle | ○ Causes vasoconstriction

Question 44

phenylephrine used for

Answer 44

○ Used clinically for relief of nasal congestion associated with acute and chronic rhinitis § Sudafed PE `

Question 45

- Salbutamol

Answer 45

○ Activates B2 on smooth muscle of airways, uterus and blood vessels ○ Primary effect is to cause relaxation of smooth muscle

Question 46

salbutamol used clinically for

Answer 46

○ Used clinically to relieve bronchoconstriction in asthma

Question 47

salbutamol given as

Answer 47

○ Typically given topically (as aerosol) directly to site of action (airways) rather than orally because § A more rapid bronchodilator response is achieved § A lower overall dose can be given (less side effects)

Question 48

antagonism of which receptors is clinically useful

Answer 48

○ A1 - antagonism for hypertension | ○ B1 - antagonism in many CV diseases

Question 49

- Prazosin

Answer 49

○ Selectively binds and inhibits a1 adrenoceptors | antagonist

Question 50

prazosin used for

Answer 50

○ Used clinically as antihypertensive agent | § Not first line treatment in hypertension

Question 51

when to take prazosin

Answer 51

○ May cause dizziness on standing, especially with initial use in the elderly Taken before bed

Question 52

tamulosin

Answer 52

§ Tamsulosin used for symptom relief in benign prostatic hypertrophy § Relaxes prostatic smooth muscle to improve blood flow § Tamsulosin has specific action against a subtype of a1 adrenoceptors