Autonomic Nervous System (Pharmacology) Flashcards
Match.
Afferent vs Efferent
Away vs Toward CNS
Afferent - Toward CNS
Efferent - Away from CNS
What are the 3 components of the ANS (Motor & Sensory)?
Sympathetic NS
Parasympathetic NS
Enteric NS
Motor ANS mediates output from CNS to whole body except?
Voluntary skeletal muscles (Under SOMATIC efferent)
Which exocrine secretion(s) is under ANS control?
All
Which common disease is associated with ANS dysfunction?
Diabetes
Match.
Fight/Flight vs Rest/Digest
Sympathetic vs Parasympathetic
Sympathetic NS - Fight/Flight functions
Parasympathetic NS - Rest & Digest
Outflow tract of SNS and PNS?
SNS - Thoracolumbar (Spinal cord)
PNS - Craniosacral (Brain stem and spinal cord)
What is the preganglionic length of SNS and PNS and where do they synapse?
SNS - Short. Synapses in pre/para-vetebral ganglia; branches extensively to synapse with postganglionic neurons –> effectors
PNS - Long. Synapse in terminal ganglia usually at walls of effector organs.
What is the postganglionic length of SNS and PNS
SNS - Long.
PNS - Short.
What are the pre and postganglionic neurotransmitters of SNS and PNS?
SNS: Pre (ACh), Post (Noradrenaline)
PNS: Pre (ACh), Post (ACh)
Appearance of preganglionic fibers of SNS and PNS?
White. Both myelinated (Motor B-fibres)
Appearance of postganglionic fibers of SNS and PNS?
Grey. Both largely un-myelinated (Motor C-fibres)
How is ACh released at the preganglionic neuron?
Voltage-gated calcium selective channel opens due to AP from CNS –> Ca2+ influx –> ACh released via exocytosis
Where does ACh bind to after release from the preganglionic neuron?
Binds to ligand-gated ion channels (Nicotinic ACh receptors) in postganglionic neuron resulting in AP –> Ca2+ influx –> Noradrenaline release to activate GPCR adrenoceptors in effector cell
What does ACh released at the postganglionic neuron bind to?
GPCR muscarinic ACh receptors in effector cell
What are the non-adrenergic, non-cholinergic (NANC) transmitters co-released alongside NA or ACh at the postganglionic fibres for SNS and PNS respectively?
SNS: ATP > NA > Neuropeptide Y
PNS: ACh > NO > VIP
**Speed of response from rapid & short-lived to slow & sustained
Are the Nicotinic ACh receptors the same as Nicotinic receptors found in neuromuscular junctions or CNS?
No
What are the 2 types of cholinoceptors?
- Nicotinic ACh receptor (LGIC)
2. Muscarinic ACh receptor (GPCR)
What is the type of all adrenoceptors?
GPCR
Rank potency of agonists on a and B adrenoceptors.
Noradrenaline, Adrenaline, Isoprenaline
a-adrenoceptor: Noradrenaline > Adrenaline > Isoprenaline
B-adrenoceptor: Isoprenaline > Adrenaline > Noradrenaline
What is found at the sympathetic chain?
Paravertebral ganglia (Synapse of pre- and post-ganglions)
What is the rate-limiting step in synthesis of ACh?
Uptake of choline via CHT transporter
What are the 2 enzymes involved in ACh synthesis?
Choline acetyltransferase (ChAT) Acetyl CoA