10 - Drugs And The Nervous System Flashcards
The nervous system allows an organism to…
Sense and respond to the environment
The peripheral nervous system (PNS) comprises the… (2)
Afferent and efferent systems (input and output)
Efferent (output) system of PNS can be divided into two branches…
Autonomic and somatic
Autonomic nervous system is divided into…
Sympathetic (fight or flight) and parasympathetic (rest and digest) branches
The somatic nervous system provides the motor innervation of…
Skeletal muscles
The autonomic nervous system is involuntary and controls…
Smooth muscle
Neurotransmitters of the sympathetic nervous system (excluding sweat glands and adrenal glands)…
Pre-ganglion = Ach Post-ganglion = Noradrenaline
Neurotransmitters for sweat glands are…
Pre-ganglion = Ach Post-ganglion = Ach
Neurotransmitters for adrenal glands…
Pre-ganglion = Ach
Adrenal medulla = Adrenaline
The neurotransmitter of the parasympathetic nervous system…
Both pre and post ganglion use acetylcholine
In the somatic efferent nervous system (e.g. skeletal muscle), the neurotransmitter released across the NMJ is…
Acetylcholine
Acetylcholine is synthesised from choline by…
Choline acetyl transferase (CAT) 😺
Acetylcholine is bound by either…
Muscarinic or nicotinic receptors
Acetylcholine is broken down at the synapse by the enzyme…
Acetylcholine esterase (AchE)
Muscarinic Ach is found at…
Post-ganglionic parasympathetic synapses
mAch receptors are coupled with…
G-proteins
Nicotinic acetylcholine receptors are divided into 2 types…
Neuronal (brain and autonomic ganglia) and muscle (NMJ)
N.b. They are both excitatory
nAch receptors are…
Ligand gated ion channels (ionotropic receptors)
Ach agonists are known as…
Parasympathomimetic
Ach antagonists are known as…
Parasympatholytic
Neuronal nicotinic agonists are not clinically useful as they…
Affect both sympathetic and parasympathetic nervous systems, causing autonomic confusion
(There are, however, clinical uses for muscle nAch agonists)
The nicotinic agonist suxamethonium and antagonist tubocurarine can both be used to…
Induce paralysis for surgery
Hyocine is a…
Muscarinic antagonist used to decrease gastric motility and treat motion sickness
The muscarinic antagonist atropine tropicamide is used for…
Pupil dilation during eye surgery (or to decrease secretions)
Pilocarpine is a muscarinic… (+ use)
Agonist used to treat glaucoma
Anticholinesterases inhibit…
Acetylcholine metabolism
Both botulinum Toxin and bungarotoxin inhibit…
Acetylcholine release (leading to parasympathetic and motor paralysis)
