Autonomic Nervous System Flashcards
Autonomic Nervous System:
- Part of the …NS
- Involuntary control:
- Regulates operation of the … organs
- Maintains … environment
- Innervates … muscle, … muscle, …
- 3 divisions:
- Sympathetic
- Parasympathetic
- … (the “little brain”)
- Part of the PNS
- Involuntary control:
- Regulates operation of the internal organs
- Maintains internal environment
- Innervates smooth muscle, cardiac muscle, glands
- 3 divisions:
- Sympathetic
- Parasympathetic
- Enteric (the “little brain”)
Autonomic Nervous System:
- Part of the PNS
- … control:
- Regulates operation of the internal organs
- Maintains internal environment
- Innervates smooth muscle, cardiac muscle, glands
- 3 divisions:
- …
- …
- Enteric (the “little …”)
- Part of the PNS
- Involuntary control:
- Regulates operation of the internal organs
- Maintains internal environment
- Innervates smooth muscle, cardiac muscle, glands
- 3 divisions:
- Sympathetic
- Parasympathetic
- Enteric (the “little brain”)
3 divisions of the ANS
- Sympathetic
- Parasympathetic
- Enteric (the “little brain”)
Autonomic function
- … function:
- Fight or flight response
- Maximises use of metabolic resources
- … function:
- Opposite to … division
- Switched on during resting
- Increases/conserves metabolic resources
- Both divisions work together to maintain the … environment
- Sympathetic function:
- Fight or flight response
- Maximises use of metabolic resources
- Parasympathetic function:
- Opposite to sympathetic division
- Switched on during resting
- Increases/conserves metabolic resources
- Both divisions work together to maintain the internal environment
Autonomic function
- Sympathetic function:
- … or … response
- Maximises use of … resources
- Parasympathetic function:
- Opposite to sympathetic division
- Switched on during …
- Increases/conserves metabolic …
- Both divisions work together to maintain the internal environment
- Sympathetic function:
- Fight or flight response
- Maximises use of metabolic resources
- Parasympathetic function:
- Opposite to sympathetic division
- Switched on during resting
- Increases/conserves metabolic resources
- Both divisions work together to maintain the internal environment
Map of the ANS
- What is para? what is sympathetic?
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- Sympathetic system is sandwiched between parasympathetic system
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- 2 Parasympathetic components - one in …, one in S2 to S4 region of spinal cord
- 1 sympathetic component - … to …. region of spinal cord
- 2 Parasympathetic components - one in brainstem, one in S2 to S4 region of spinal cord
- 1 sympathetic component - T1 to L2 region of spinal cord
General autonomic circuit
- Axons do not pass directly to the … organs
- They form … pathways
- EXCEPT … supply to adrenal medulla
- Axons do not pass directly to the effector organs
- They form disynaptic pathways
- EXCEPT sympathetic supply to adrenal medulla
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General autonomic circuit
- Axons do not pass directly to the effector organs
- They form disynaptic pathways
- EXCEPT sympathetic supply to … …
- Axons do not pass directly to the effector organs
- They form disynaptic pathways
- EXCEPT sympathetic supply to adrenal medulla
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Neurotransmission - ANS
- Many of the receptors within the ANS provide targets for drugs
- Within autonomic ganglia:
- … is the main neurotransmitter (Although lots of neuropeptides)
- Binds to nicotinic receptors on postganglionic neurons
- Ionotropic ligand-gated (fast): … opens pore, depolarises neuron
- Many of the receptors within the ANS provide targets for drugs
- Within autonomic ganglia:
- Acetylcholine is the main neurotransmitter (Although lots of neuropeptides)
- Binds to nicotinic receptors on postganglionic neurons
- Ionotropic ligand-gated (fast): Acetylcholine opens pore, depolarises neuron
Neurotransmission - ANS
- Many of the receptors within the ANS provide targets for drugs
- Within … …:
- Acetylcholine is the main neurotransmitter (Although lots of neuropeptides)
- Binds to nicotinic receptors on … neurons
- Ionotropic ligand-gated (fast): Acetylcholine opens pore, … neuron
- Many of the receptors within the ANS provide targets for drugs
- Within autonomic ganglia:
- Acetylcholine is the main neurotransmitter (Although lots of neuropeptides)
- Binds to nicotinic receptors on postganglionic neurons
- Ionotropic ligand-gated (fast): Acetylcholine opens pore, depolarises neuron
Neurotransmission - ANS
- Postganglionic sympathetic neurons:
- … is the main neurotransmitter (except sweat glands use acetylcholine)
- Binds to adrenergic receptors on the effector organ
- … G-protein coupled (slow)
- There are multiple subtypes: a1, a2, B1, B2 and B3
- Postganglionic sympathetic neurons:
- Noradrenaline is the main neurotransmitter (except sweat glands use acetylcholine)
- Binds to adrenergic receptors on the effector organ
- Metabotropic G-protein coupled (slow)
- There are multiple subtypes: a1, a2, B1, B2 and B3
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Neurotransmission - ANS
- Postganglionic sympathetic neurons:
- Noradrenaline is the main neurotransmitter (except sweat glands use …)
- Binds to … receptors on the effector organ
- Metabotropic G-protein coupled (…)
- There are multiple subtypes: a1, a2, B1, B2 and B3
- Postganglionic sympathetic neurons:
- Noradrenaline is the main neurotransmitter (except sweat glands use acetylcholine)
- Binds to adrenergic receptors on the effector organ
- Metabotropic G-protein coupled (slow)
- There are multiple subtypes: a1, a2, B1, B2 and B3
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- A1 - Blood vessels: a1 antagonists used to treat … (E.g. Prazosin)
- B1 - Heart: B1 antagonists used to treat … (E.g. Atenolol)
- B2 - Bronchus: B2 agonists used to treat … (E.g. Salbutamol)
- A1 - Blood vessels: a1 antagonists used to treat hypertension (E.g. Prazosin)
- B1 - Heart: B1 antagonists used to treat hypertension (E.g. Atenolol)
- B2 - Bronchus: B2 agonists used to treat asthma (E.g. Salbutamol)
Neurotransmission -Within adrenal medulla
- … is also the main neurotransmitter
- Binds to nicotinic receptors on … cells
- Causes release of adrenalin/noradrenalin into circulation
- Direct activation of sympathetic effector organs
- Acetylcholine is also the main neurotransmitter
- Binds to nicotinic receptors on chromaffin cells
- Causes release of adrenalin/noradrenalin into circulation
- Direct activation of sympathetic effector organs
Neurotransmission -Within adrenal medulla
- Acetylcholine is also the main neurotransmitter
- Binds to nicotinic receptors on chromaffin cells
- Causes release of …/… into circulation
- … activation of sympathetic effector organs
- Acetylcholine is also the main neurotransmitter
- Binds to nicotinic receptors on chromaffin cells
- Causes release of adrenalin/noradrenalin into circulation
- Direct activation of sympathetic effector organs
Neurotransmission - ANS - Postganglionic sympathetic neurons
- … is the main neurotransmitter
- Binds to … receptors on the effector organ
- … G-protein coupled (slow)
- Cholinergic-muscarinic antagonist (e.g. Atropine) are used to treat bradycardia, dilate pupils, reduce glandular secretions etc.
- Acetylcholine is the main neurotransmitter
- Binds to muscarinic receptors on the effector organ
- Metabotropic G-protein coupled (slow)
- Cholinergic-muscarinic antagonist (e.g. Atropine) are used to treat bradycardia, dilate pupils, reduce glandular secretions etc.
…-muscarinic … (e.g. Atropine) are used to treat bradycardia, dilate pupils, reduce glandular secretions etc.
Cholinergic-muscarinic antagonist (e.g. Atropine) are used to treat bradycardia, dilate pupils, reduce glandular secretions etc.
Sympathetic system - ANS
- Huge system
- Cardiac muscle - … pacemaker activity + contractile force
- Bronchi of lungs - broncho…
- Sweat glands - sweat …
- Hair follicles - piloerection
- Blood vessels - vaso… of arteries/arterioles
- Abdomino-pelvic viscera - inhibits peristalsis + gastric secretion, stimulate glucagon secretion, stimulates secretion of adrenalin
- Eye - … pupils
- Huge system
- Cardiac muscle - increases pacemaker activity + contractile force
- Bronchi of lungs - bronchodilation
- Sweat glands - sweat secretion
- Hair follicles - piloerection
- Blood vessels - vasoconstriction of arteries/arterioles
- Abdomino-pelvic viscera - inhibits peristalsis + gastric secretion, stimulate glucagon secretion, stimulates secretion of adrenalin
- Eye - dilates pupils
Sympathetic system - ANS
- Huge system
- Cardiac muscle - … pacemaker activity + contractile force
- Bronchi of lungs - bronchodilation
- Sweat glands - sweat …
- Hair follicles - pilo…
- Blood vessels - vasoconstriction of arteries/arterioles
- Abdomino-pelvic viscera - … peristalsis + gastric secretion, … glucagon secretion, … secretion of adrenalin
- Eye - … pupils
- Huge system
- Cardiac muscle - increases pacemaker activity + contractile force
- Bronchi of lungs - bronchodilation
- Sweat glands - sweat secretion
- Hair follicles - piloerection
- Blood vessels - vasoconstriction of arteries/arterioles
- Abdomino-pelvic viscera - inhibits peristalsis + gastric secretion, stimulate glucagon secretion, stimulates secretion of adrenalin
- Eye - dilates pupils
Sympathetic trunk/chain
- Interconnected … ganglia close to bodies of vertebrae
- Extends from cervical to sacral levels
- Preganglionic fibres enter sympathetic trunk through … rami communicantes
- Interconnected paravertebral ganglia close to bodies of vertebrae
- Extends from cervical to sacral levels
- Preganglionic fibres enter sympathetic trunk through white rami communicantes
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Preganglionic fibres
- On entering the trunk, preganglionic fibres either:
- Synapse in … - same level or travel to another level OR
- Pass through ganglion into splanchnic nerves to synapse in … ganglia
- On entering the trunk, preganglionic fibres either:
- Synapse in ganglion - same level or travel to another level OR
- Pass through ganglion into splanchnic nerves to synapse in prevertebral ganglia
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Preganglionic fibres
- On entering the trunk, preganglionic fibres either:
- … in ganglion - same level or travel to another level OR
- … … ganglion into splanchnic nerves to synapse in prevertebral ganglia
- On entering the trunk, preganglionic fibres either:
- Synapse in ganglion - same level or travel to another level OR
- Pass through ganglion into splanchnic nerves to synapse in prevertebral ganglia
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Preganglionic fibres
- On entering the trunk, preganglionic fibres either:
- Synapse in ganglion - same level or travel to another level OR
- Pass through ganglion into splanchnic nerves to synapse in … …
- On entering the trunk, preganglionic fibres either:
- Synapse in ganglion - same level or travel to another level OR
- Pass through ganglion into splanchnic nerves to synapse in prevertebral ganglia
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