Autonomic nervous system Flashcards
Autonomic nervous system is a set of pathways to and from CNS that innervates and regulates
- SMC
- cardiac muscle
- Glands
ANS - Synapse between neurons are made in the
autonomic ganglia
ANS - sympathetic vs parasympathetic ganglia according to location
parasympathetic –> in or near the effector organ
sympathetic –> in the paravertebral chain
ANS - Pregaglionic neurons - location (generally)
- cell bodies in the CNS
- synapse in autonomic ganglia
ANS - sympathetic vs parasympathetic preganglionic neurons according to origin
Symp –> spinal cord T1 - L3 (thoracocolumnar region)
Para –> nuclei of cranial nerves (3, 7, 9, 10) + spinal cord S2-S4 (craniosacral region)
cranial nerves with parasympathetic nervous system
3, 7, 9, 10
ANS - sympathetic vs parasympathetic preganglionic and postgnanglionic neurons according to size
parasympathetic –> long pre, short post
sympathetic –> short pre, long post
ANS - postganglionic neurons - location (generally)
- cell bodies in the autonomic ganglia
- synapse on effector organs
Neurotransmitters of ANS (and receptors)
- all preganglionic neurons secrete ACH (nicotinic)
- parasympahtetic postganglionic secrete ACH (M)
- sympathetic postganglionic secrete norepinephrine (α1, α2, β1), dopamine (D1), ACH (M, in sweat glands)
ANS - neurotransmitter and receptor type in ganglion
ACH / nicotinic (Nn)
ANS - adrenal medulla
sympathetic preganglionic neuron synapse there with ACH (Nicotinic), causing Norepinephrine and epinephrine releasing in blood
ANS - sympathetic postganglionic - ACH - target?
sweat glands (M receptor)
ANS - sympathetic postganglionic - Dopamine - target?
- renal vasculature
2. smooth muscle
ANS - sympathetic postganglionic - NE - target?
cardiac and smooth muscle, gland cells, nerve terminal
target of Norepinephrine and epinephrine released by adrenal medulla
cardiac muscle
vessels
targets of parasympathetic nervous systme
- Cardiac muscle
- smooth muscle
- gland cells
- nerve terminals
organs that are part of sympathetic nervous system but are innervated by ACH
- adrenal medulla
2. sweat glands
Botulinum toxin - mechanism of action
protease that cleave SNARE (soluble NSF attachment protein receptor), a set of proteins required for neurotransmitter release via vesicular formation –> prevent release of stimulatory (ACH) signals at neuromuscular junctions (and ANS)
neuromascular juction receptor vs autonomic ganglion receptor
both Ach:
ganglion: Nn
NMJ: Nm
types of ACH receptors and their types
- Nicotinic: a. Nn b. Nm
2. Muscarinic: M1-5
types of ACH receptors and their pathway
- Nicotinic: ligant gated Na/K channel
2. Muscarinic: G-protein coupled receptors
types of ACH receptors and their location
- Nicotinic: a. Nn autonomic on ganglia and adrenal medulla b. Nm on NMJ
- Muscarinic in heart, smooth muscle, brian, exocrine glands, sweat glands
G protein - linked 2nd messengers - type of receptors (only the groups)
- sympathetic
- parasympathetic
- dopamine
- histamine
- vasopressin