cholinergic and adrenergic pharmacology

Question 1

what are Cholinergic and adrenergic pharmacology responsible for

Answer 1

1. control of blood pressure
2. control of heart rate
3. anaesthetic agents
4. regulation of airway tone
5. pressures in the eye
6. control of gI function

Question 2

how do Cholinergic and adrenergic pharmacology control blood pressure

Answer 2

raise it in shock, lower it in hypertension

Question 3

how do Cholinergic and adrenergic pharmacology control heart rate

Answer 3

speed up lethal bradycardias, slow down dangerous tachycardias

Question 4

how do Cholinergic and adrenergic pharmacology control anaesthetic agents

Answer 4

muscle relaxants

Question 5

how do Cholinergic and adrenergic pharmacology regulate airway tone

Answer 5

treat life threatening bronchospasm

Question 6

how do Cholinergic and adrenergic pharmacology work with eye pressure

Answer 6

prevent glaucoma causing blindness

Question 7

how do cholinergic and adrenergic pharmacology control Gi function

Answer 7

diarrhoea and constipation

Question 8

how many neurones innervate muscle in the somatic nervous system

Answer 8

one neurone comes from the CNS to innervate muscle

Question 9

how many neurones innervate muscle in the autonomic nervous system

Answer 9

there are two nerves in series: pre and post-ganglionic fibres

Question 10

describe parasympathetic ganglia

Answer 10

are near their targets with short post-ganglionic nerves,

Question 11

describe sympathetic ganglia

Answer 11

are near the spinal cord with longer post-ganglionic fibres

Question 12

describe the parasympathetic nervous system

Answer 12

Cranial nerves like the oculomotor nerve, facial nerve and vagus nerve carry signals to the body

A further sacral outflow innervates the pelvis

Short post-synaptic nerve fibres reach the targets and release acetylcholine (ACh), which acts on muscarinic receptors of various subtypes

Question 13

describe the sympathetic nervous system

Answer 13

Regulates the fight-and-flight response

Nerve fibres originating in the spinal cord terminate in ganglia near the cord, then send out long nerve fibres to blood vessels, muscles etc.

They release noradrenaline which activates adrenergic receptors, of which there are two main types (alpha/ beta) with subtypes

Question 14

what are mediators of the nervous system

Answer 14

acetylcholine and
noradenrelaine

Question 15

what do Parasympathetic and sympathetic fibres coming out of the CNS release

Answer 15

both release ACh

acts on nicotinic receptors

Question 16

what do post-ganglionic parasympathetic fibres release

Answer 16

more acetylcholine

acting on muscarinic receptors

Question 17

what do post-ganglionic sympathetic fibres release

Answer 17

noradrenaline

acting on alpha and beta adrenoceptors

Question 18

describe muscarinic receptors

Answer 18

M1-5; GPCRs

G proteins can activate various types of second messenger signals with different consequences for the cells

The G-Protein-Coupled Receptor structure is widely used in the body for signalling

Question 19

where are M1 receptors

Answer 19

mainly in the brain

Question 20

where are M2 receptors

Answer 20

mainly in the heart. (their activation slows the heart, so we can block these)

Question 21

where are M3 receptors

Answer 21

glandular and smooth muscle. (cause bronchoconstriction, sweating, salivary gland secretion

Question 22

where are M4/5 receptors

Answer 22

mainly in the CNS

Question 23

what causes Anti-cholinergic side effects

Answer 23

Many drugs have some anticholinergic activity and side-effects through these pathways

Question 24

what are anti-cholinergic side effects in the brain

Answer 24

anticholinergics worsen memory and may cause confusion

Question 25

what are anti-cholinergic side effects peripherally

Answer 25

• get constipation
• drying of the mouth
• blurring of the vision
• worsening of glaucoma

Question 26

what are alpha agonists

Answer 26

substances that activate the sympathetic nervous system by stimulation of alpha receptors

Question 27

what does alpha 1activation cause

Answer 27

vasoconstriction, particularly in the skin and splanchnic beds: less so in brain, lung, heart

Question 28

what does adrenaline do

Answer 28

will raise blood pressure and cardiac work in other settings

Question 29

what occurs in nasal decongestion

Answer 29

topical alpha activation

Question 30

impact of alpha 1 on blood pressure

Answer 30

raises it

Question 31

impact of alpha 2 on blood pressure

Answer 31

lowers it

Question 32

what does an alpha blocker do

Answer 32

opposite effect to the agonists

Block alpha 1 to lower blood pressure: doxazosin
Tamsulosin blocks a specific subtype (alpha 1A) in the prostate, to help treat prostatic hypertrophy

Question 33

impact of beta 1 activation

Answer 33

activation will increase heart rate and chronotropic effects, and may increase risk of arrhythmias

Question 34

impact of beta 2 activation

Answer 34

activation is life saving in asthma, and can delay onset of premature labour

Question 35

impact of beta 3 agonists

Answer 35

can reduce over-active bladder symptoms

Question 36

what do beta blockers do

Answer 36

Lower blood pressure (reduction in cardiac output reduction in central sympathetic outflow activity), reduce cardiac work, treat arrhythmias

Question 37

can drugs have mixed alpha and beta blockers

Answer 37

yes
Some drugs have mixed alpha/ beta blocking roles with varying theoretical benefits

Question 38

uses of beta blockers

Answer 38

Angina
MI prevention
High blood pressure
Heart failure

Question 39

side effects of beta blokcers

Answer 39

Tiredness
Bronchoconstriction
Bradycardia
Cardiac depression