Autonomic nervous system

Question 1

What is the CNS composed of?

Answer 1

brain and spinal cord

Question 2

What is the peripheral nervous system composed of?

Answer 2

nerve cells carrying information to or from the CNS

Question 3

Describe the input of the autonomic nervous system

Answer 3

input- neurons associated with interoceptors such as chemoreceptors,mechanoreceptors, thermoreceptors, nociceptors

Question 4

Describe the output of the autonomic nervous system

Answer 4

-via motor neurons to
-cardiac muscle,smooth muscle,glands
-most organs have dual sympathetic and parasympathetis intervention

Question 5

Describe the function of the ANS in the heart

Answer 5

-symp- HR and force increases
-para- HR and force decreases

Question 6

Describe the function of the ANS in the iris

Answer 6

symp- pupil dilation
para-pupil constriction

Question 7

Describe the function of the ANS in the salivary glands

Answer 7

symp-reduced saliva production
para-increased saliva production

Question 8

Describe the function of the ANS in oral and nasal mucosa

Answer 8

symp-reduced mucus production
para-mucus production increased

Question 9

Describe the function of the ANS in the lungs

Answer 9

symp-bronchial muscle relaxed
para-bronchial muscle contracted

Question 10

Describe the function of the ANS in the stomach

Answer 10

symp- peristalsis reduced
para- gastric juice secreted, motility increased

Question 11

Describe the function of the ANS in the intestines

Answer 11

symp-motility reduced
para-digestion increased, secretion and motility increased

Question 12

Describe the function of the ANS in the kidney

Answer 12

symp-decreased urine secretion
para-increases urine secretion

Question 13

Describe the structure of the SNS preganglionic neurons

Answer 13

-cell bodies in the lateral horns of grey matter in spinal cord of the:
-12 thoracic segment
-first 2-3 lumber segments of the thoracolumbar division

Question 14

Describe the structure of the PSNS preganglionic neurons

Answer 14

cell bodies found in the nuclei od:
-four cranial nerves (III, VII, IX, X)
-lateral grey horns of the 2nd-4th sacral segments
-craniosacral division

Question 15

Whats the difference between the preganglionic neurons and postganglionic neurons?

Answer 15

pre are short and post are long

Question 16

Describe the structure of the sympathetic trunk ganglia

Answer 16

-lie in a vertical row alongside the vertabrae from skull to cocyx
-innervate organs above the diaphragm

Question 17

Describe the structure of the collateral prevertebral ganglia

Answer 17

-lie in front of the vertebral column alongside abdominal muscles
-celiac ganglion
-superior and inferior mesenteric ganglion
-innervate organs below the diaphragm

Question 18

Describe the parasympathetic ganglia structure

Answer 18

-located close to effector organs
-preganglionic axons are longer than sympathetic preganglionic fibres

Question 19

List the key parts of synapses

Answer 19

-axon terminal
-synaptic vesicle
-transporter
-neurotransmitter
-synaptic cleft
-receptor
-postsynaptic neuron

Question 20

Name the neurotransmitters in the ANS

Answer 20

-ACH
-Noradrenaline

Question 21

List the neurotransmitters in the PSNS and the receptors

Answer 21

-ACH

-nicotinic receptors
-muscarinic receptors
-effector cells

Question 22

List the neurotransmitters and receptors in the SNS

Answer 22

-ACH
-Noroadrenaline

-nicotinic receptor, adrenergic receptors,effector cells

-pre and post ganglion neuron

Question 23

Describe what releases ACh

Answer 23

-both para and symp preganglionic neurons
-released by parasympathetic postganglion neurons and sympathetic postganglion neurons which innervate sweat glands

Question 24

Describe the two types of ACh receptors

Answer 24

Nicotinic receptor
-symp and para ganglia
Muscarinic receptors
-plasma membrane of effector organs innervayed by PSNS
-membrane of sweat glands innervated by Symp postganglionic neurons

Question 25

Describe Noraadrenaline

Answer 25

Noradrenaline= Norepinephrine
-released by symp postganglionic neurons
-acts at adrenergic receptors at effector organs
-broken down cathechol-o methyltransferase (COMT)
-two main group of adrenergic receptor- alpha and beta with subtypes

Question 26

Describe the location and action of the adrenergic receptor a1

Answer 26

location-vascular smooth muscle
action-increased vascular smooth muscle contraction

Question 27

Describe the location and action of the adrenergic receptor a2

Answer 27

location-CNS
action-decreased sympathetic outflow

Question 28

Describe the location and action of the adrenergic receptor B1

Answer 28

location-cardiac cells
Action-increased HR, increased contractility, increased renin release

Question 29

Describe the location and action of the adrenergic receptor B2

Answer 29

location-bronchiole smooth muscle, vascular smooth muscle
-action-bronchodilation,vasodilation

Question 30

Describe the location and action of the adrenergic receptor B3

Answer 30

location-adipose tissue,bladder and gallbladder
action-increased lipolysis, relaxation of the bladder

Question 31

Describe bronchodilator mechanisms

Answer 31

Beta 2 receptor agonist
-works on SNS
-Drug(sambutanol) binds to receptor
-receptor stimulates Gprotein to activate adenyl cyclase
-adenyl cyclase converts ATP to cAMP
-cAMP relases smooth muscle by:
-inhibits release of ca2+ from sarcoplasmic recticulum
-activates protein kinase A
-protein kinase A inactivates myosin light chain kinase-prevents actin-myosin interaction
-smooth muscle relaxation

Question 32

Describe the bronchodilator mechanism at the muscarinic receptor

Answer 32

-ACh binds to muscarinic receptors
-receptors stimulate G protein to activate phospholipase C
-Phospholipase C stimulates production of inositol phosphate (IP3)
-IP3 binds to sarcoplasmic recticulum and stimulates release of Ca2+-contraction
-phospholipase C also leads to activation of myosin light chain kinase which causes a contraction

Question 33

Describe the effects of anti cholinergic drugs in bronchodilator mechanisms

Answer 33

block the casacade reducing resting Paraympathetic bronchial tone resulting in bronchodilation
-ipratopium bromide-atrovent