Autonomic Nervous System Flashcards
What is a ganglion?
A group of nerve cell bodies in the PNS
What is the hindbrain?
Important gateway of nerves between the spinal cord and cortex
What are the three neural outputs of the CNS?
Somatic motor, sympathetic and parasympathetic
When is the sympathetic division most active?
During exercise/stress
The sympathetic nervous system has what kind of responses?
Fight or flight
Name some of the flight or fight responses
Increased heart rate, increased blood pressure, increased blood flow to muscles, increased blood sugar levels, inhibition of GI peristalsis, relaxed airways, pupil dilation and orgasm.
The parasympathetic nervous system has what kind of responses?
Rest and digest
Name some of the rest and digest responses
Decreased heart rate, Increased GI motility, bronchial constriction, pupil constriction and gastric acid secretion.
In terms of energy what happens in the sympathetic nervous system?
Energy is used by various activities
In terms of energy what happens in the parasympathetic nervous system?
Energy is conserved
During action potential have happens to the voltage/membrane potential of the inside of the neurone?
It becomes more positive
Which ions move into the cell during an action potential?
Sodium
Receptors in target tissue of the SNS detect and respond to which neurotransmitter?
Noradrenaline
Receptors in target tissue of the PNS detect and respond to which neurotransmitter?
Acetylcholine
Which neurotransmitter is used in all preganglionic neurons?
Acetylcholine
Nicotine can stimulate which agonist receptors?
Acetylcholine receptors
Where are nicotinic receptors found?
CNS, ANS ganglia and the neuromuscular junction
What are the two classes of acetylcholine receptors?
Nicotinic and muscarinic
What are the locations of muscarinic receptors?
Target tissues of the parasympathetic postganglionic neurons
Muscarinic receptors are blocked by…
Atropine
Nicotinic receptors are blocked by…
Curare
What is atropine?
An alkaloid atropa belladonna
What is the general organisation of the pathway of the sympathetic nervous system?
Spinal cord -> ganglion with nicotinic acetylcholine receptors -> target tissue with adrenergic receptors
The adrenal gland can be associated with which nervous system?
Sympathetic nervous system
Stress can cause hormones to be released from where?
The brain and the adrenal cortex
Cortisol is released by what?
The adrenal cortex
Cocaine is a stimulant drug that enhances sympathetic effects. How?
By prolonging the action of neurotransmitters like noradrenaline, serotonin and dopamine in the PNS and CNS
Amphetamine is a psychostimulant. How does this work?
By prolonging the action of neurotransmitters like noradrenaline, serotonin and dopamine mainly in the CNS.
What is the general organisation of the pathway of the parasympathetic nervous system?
Spinal cord -> ganglion with nicotinic acetyl choline receptors -> target tissue with muscarinic acetylcholine receptors
The enteric division, also known as the ‘little brain’ is made up of 2 complex networks. What are they?
Myenteric plexus and submucous plexus
What does the enteric division control?
Processes in food transport and digestion from mouth to anus
What is/are the main neurotransmitter(s) in the sympathetic system?
Noradrenaline and acetylcholine
What is/are the main neurotransmitter(s) in the parasympathetic system?
Acetylcholine
Is the preganglionic neuron in the sympathetic NS long or short?
Short
Is the preganglionic neuron in the parasympathetic NS long or short?
Long
What is the location of the ganglia in the sympathetic NS?
Paravertebral
What is the location of the ganglia in the parasympathetic NS?
Close to the effector
What are the metabolic/physiological effects of the sympathetic NS?
Catabolic (fight/flight)
What are the metabolic/physiological effects of the parasympathetic NS?
Anabolic (rest and digest)
Name some autonomic nervous system problems
Orthostatic hypotension, inability to sweat/excess sweating, constipation and impotence.
What are some of the causes of autonomic nervous system problems?
Diabetes, old age, drugs, autoimmune degradation of nerves, spinal injury and brain tumours.
