Drugs and the Parasympathetic Nervous System Flashcards
Decide whether each of the clinical uses listed below should be classified under muscarinic receptor agonism or antagonism.
Pilocarpine and cevimeline that stimulate salivation and lacrimation in patients with a dry mouth or eyes, secondary to irradiation or Sjögren’s syndrome
Muscarinic receptor agonist
Decide whether each of the clinical uses listed below should be classified under muscarinic receptor agonism or antagonism.
Darifenacin used in the treatment of urinary incontinence to relax the bladder
Muscarinic receptor antagonist
Decide whether each of the clinical uses listed below should be classified under muscarinic receptor agonism or antagonism.
Tiotropium and ipratropium used as bronchodilators for the treatment of asthma and COPDilation to facilitate ophthalmoscopic examination
Muscarinic receptor antagonist
Decide whether each of the clinical uses listed below should be classified under muscarinic receptor agonism or antagonism.
Pilocarpine eye drops that cause a reduction in intraocular pressure and are used in the treatment of glaucoma
Muscarinic receptor agonist
Decide whether each of the clinical uses listed below should be classified under muscarinic receptor agonism or antagonism.
Agents used to reduce salivation and bronchial secretions as premedication for anaesthesia
Muscarinic receptor antagonist
Decide whether each of the clinical uses listed below should be classified under muscarinic receptor agonism or antagonism.
Agents used for pupillary dilation to facilitate ophthalmoscopic examination
Muscarinic receptor antagonist
The parasympathetic system:
Has minimal effect on the bronchial tree
False. The parasympathetic system stimulates bronchoconstriction.
The parasympathetic system:
Increases heart rate
False. The parasympathetic system slows the heart.
The parasympathetic system:
Relaxes the bladder
False. The parasympathetic system contracts the bladder.
The parasympathetic system:
Stimulates erection and ejaculation
False. The sympathetic system controls ejaculation.
The parasympathetic system:
Constricts the pupil
True
The parasympathetic system:
Increases gastric secretion
True
Regarding the neurotransmitters that affect the parasympathetic nervous system:
Ganglionic receptors are exclusively nicotinic
False. Neurotransmission at autonomic ganglia is predominantly nicotinic, but muscarinic receptors are present and increase excitation.
Regarding the neurotransmitters that affect the parasympathetic nervous system:
Botulinism results from the toxin preventing synthesis of acetylcholine
False. Botulism prevents the release of the acetylcholine stores.
Regarding the neurotransmitters that affect the parasympathetic nervous system:
Neurotransmission in the parasympathetic system is terminated by re-uptake of transmitter
False. The parasympathetic neurotransmitter is ACh and its effects are terminated by metabolism, not re-uptake.
Regarding the neurotransmitters that affect the parasympathetic nervous system:
The main neurotransmitter throughout the parasympathetic system is acetylcholine
True
Regarding the neurotransmitters that affect the parasympathetic nervous system:
Peripheral benzodiazepine receptors are an important site of modulation for the parasympathetic system
False. The benzodiazepine receptor may influence central control of the the autonomic system, but there is no peripheral effect.
Regarding the neurotransmitters that affect the parasympathetic nervous system:
ATP and VIP are examples of NANC transmitters
True
Regarding drugs clinicians use to affect parasympathetic activity:
Anticholinergic eye drops can be used to treat glaucoma
False. Anticholinergic drugs dilate pupils to facilitate ophthalmic examinations, but they increase intraocular pressure. Cholinergic agonists are used to treat glaucoma.
Regarding drugs clinicians use to affect parasympathetic activity:
Muscarinic antagonists can be used to treat urinary incontinence
True. The selective M3 antagonist darifenacin is used to treat urinary incontinence.
Regarding drugs clinicians use to affect parasympathetic activity:
Quaternary ammonium muscarinic antagonists do not affect the eye
False. The effects of quaternary ammonium muscarinic antagonists on the eye are mediated through the peripheral nervous system.
Regarding drugs clinicians use to affect parasympathetic activity:
Neostigmine enhances ganglionic transmission
True. Neostigmine enhances ganglionic transmission. However, the enhancement is an unwanted effect.
Regarding drugs clinicians use to affect parasympathetic activity:
Ipratropium is an acetylcholine analogue that stimulates post-synaptic receptors to produce bronchodilation
False. Ipratropium is an antagonist of acetylcholine that causes bronchodilation through inhibition of post-synaptic receptors.
Regarding drugs clinicians use to affect parasympathetic activity:
Glycopyrronium is often used to reverse the effects of neuromuscular blocking drugs
False. glycopyrronium is often given to reverse/offset the unwanted effects of neostigmine. It is neostigmine that is commonly used to reverse the effects of neuromuscular blocking drugs.
