Parasympathetic NS

Question 1

what is antagonistic control?

Answer 1

the sympathetic and parasympathetic systems having opposing effects

Question 2

what is the order of a nervous impulse in the parasympathetic NS?

Answer 2

CNS to the NIC receptor in the ganglia, to the M receptor to the effector

Question 3

what kind of receptor is a Muscarinic receptor?

Answer 3

a G-protein coupled receptor

Question 4

what are M1 receptors?

Answer 4

neural receptors that are located in the brain and the stomach

Question 5

what are M2 receptors?

Answer 5

cardiac receptors that are located in the heart

Question 6

what are M3 receptors?

Answer 6

smooth muscle receptors that are located in the ey, GI tract, bladder and the lungs

Question 7

what are the choline esters receptor agonists?

Answer 7

acetylcholine, methacholine, carbachol and bethanechol

Question 8

why is acetylcholine not used?

Answer 8

has an effect on nicotinic and Muscarinic receptors so all subtypes are stimulated and is short lived due to being effected by AChE

Question 9

what are the features of methacholine?

Answer 9

not effected by AChE so longer lasting effects and has the most Muscarinic action

Question 10

what are the features of carbachol?

Answer 10

causes nicotinic action when other don’t

Question 11

what is bethanechol used to treat?

Answer 11

glaucoma

Question 12

what effects does bethanechol have?

Answer 12

increases GI peristalsis and bladder contraction

Question 13

what are the adverse effects of bethanechol?

Answer 13

colic, diarrhoea, low BP, bronchoconstriction and sweating

Question 14

what are the alkaloid Muscarinic agonists?

Answer 14

muscarine, pilocarpine and arecoline

Question 15

what is pilocarpine used for? how does it work?

Answer 15

treatment of glaucoma, it is lipid soluble so is able to penetrate the cornea and constrict the pupillae muscle

Question 16

what is the effect of arecoline?

Answer 16

has Muscarinic and nicotonic effects on the CNS

Question 17

what are the Muscarinic effects caused by agonists?

Answer 17

pupil constriction, lower heart rate, increased GI motility, salivation, bronchoconstriction and bladder contraction

Question 18

what are the key features of the Muscarinic agonists that are used clinically?

Answer 18

stimulate muscarinic receptors with little effect on nicotinic receptors, are not broken down by AChE, have prolonged action

Question 19

what can muscarinic antagonists be used to treat?

Answer 19

bradycardia, during anaesthesia to block vagal slowing of the heart and to promote bronchodilation in

Question 20

what are the side effects of muscarinic antagonists?

Answer 20

dry mouth, constipation and urinary retention, tachycardia

Question 21

what are subtype selective muscarinic antagonists?

Answer 21

drugs that have been developed so that they are more selective for one particular subtype

Question 22

what are examples of subtype selective antagonists?

Answer 22

pirenzepine and darifenacin

Question 23

what does pirenzepine do?

Answer 23

blocks M1 receptors that are involved in gastric acid secretion

Question 24

what can pirenzepine be used for?

Answer 24

anti-ulcer treatment

Question 25

what does darifanacin do?

Answer 25

selectively blocks M3 receptors

Question 26

what is darifanacin used for?

Answer 26

to treat urinary incontinence due to inhibiting parasympathetic contraction of the bladder