ANS (autonomic Nervous System) Flashcards
What is the ANS?
All those neural pathways that leave the brain but don’t innervate voluntary muscles
ANS is split into two sections?
Sympathetic and parasympathetic
What is sympathetic system?
Fight or flight system
What is the parasympathetic system?
Rest and digest
What is a ganglion?
Mass of cell bodies found outside the CNS
Sympathetic ganglia found where?
Dorsal horn
Parasympathetic ganglia are found?
Near or inside the targets they innervate
What is the amygdala?
Main region of brain for emotions
What are exceptions in the sympathetic nervous system?
Kidneys and adrenal gland
Why is the kidney an exception in sympathetic nervous system?
Directly release dopamine onto vascular bed smooth muscle
Why is the adrenal gland an exception in sympathetic nervous system?
It is an exception because acetylcholine is released directly onto the gland to activate nicotinic receptors
What neurotransmitter is used at excitatory transmission of autonomic ganglia?
Acetylcholine on nicotinic acetylcholine receptors
Transmission at postganglionic sympathetic synapse involves what neurotransmitter?
Noradrenaline on either alpha/beta adrenoreceptors
Transmission at parasympathetic synapse usually involves what neurotransmitter?
Acetylcholine working on muscarinic receptors
What is the enteric nervous system?
Regulate gastrointestinal tract, express mechano /chemoreceptors involved in pathways that regulates input independently of neural input
What isn’t noradrenaline used for in sympathetic synapses?
Sweat glands and vasodilation
Synthesis of nor/adrenaline?
Tyrosine, L-Dopa, dopamine, noradrenaline then Adrenaline
Enzymes used for not/adrenaline production?
Tyrosine hydroxylase
Dopadecarboxylase
Dopamine betahydroxylase
PNMT
Drugs that interfere with catecholine synthesis?
Alpha-methyl-tyrosine (inhibits tyrosine hydroxylase)
Alpha-methyl-dopa (leads false transmitters?
How is noradrenaline reuptake out of synapse?
By: Extraneuronal cells (high capacity) Nerve terminal (low capacity)
How does nerve terminal reup take the noradrenaline?
Noradrenaline transporter (NAT) require ATP and sodium
How does noradrenaline uptake occur at extra neuronal tissue?
By passive means, inhibited by cortisol
