Lecture 3: Autonomic Nervous System Flashcards
Where can we find cues for the afferent (sensory) neurons?
Visual Cues Auditory Cues Baroreceptors (blood pressure) Chemoreceptors (oxygen levels) Stretch of smooth muscles
Where in the brain are autonomic responses processed?
Hypothalamus
What composes the autonomic reflex arc?
Afferent (sensory) neuron
α-motor neuron
In the ANS, how many neurons are between the CNS and end organ (target)?
2 Neurons: Pre-synpatic and Post-synaptic
aka Pre-ganglionic and Post-ganglionic
Where is the cell body of pre-synaptic neuron?
Where does it terminate?
Cell body in CNS
Terminates in a ganglion in periphery
Where is the cell body of post-synaptic neuron?
Where does it terminate?
Cell body in ganglion
Terminates at the end organ (target)
Where are the two synapses happening?
Synapse 1: Ganglion
Synapse 2: End organ (target)
Which synapse is the same between sympathetic and parasympathetic systems?
Synapse 1 at the ganglion
What neurotransmitter is released between the pre-synaptic and post-synaptic neurons?
What receptor does the post-synaptic cell have for this NT?
Acetylcholine
Nicotinic Cholinergic Receptors
What is the difference between an en passant synapse and regular neural synapses?
En passant synapse are located anywhere on the axon while regular neural synapses happen at axon terminal
-Both do the same exact thing, just have different structure
How is NT release different between NMJ and varicosities?
NMJ: NT released into synaptic cleft and goes directly to receptors on post-synaptic cells
Varicosities: NT released and are diffused until it finds receptors on post-synaptic cells
In the parasympathetic system, what NT is released from the post-synaptic cell and received by the end target organ?
What receptors does the end target organ have?
Acetylcholine
Muscarinic Cholinergic Receptors
What type of receptors are M1R, M3R, and M5R?
Gq Muscarinic acetylcholine receptors
-Increase Calcium in cell
What type of receptors are M2R and M4R?
Gi Muscarinic acetylcholine receptors
-Opens Potassium channels and can hyperpolarize cell
What structures have M1 receptors?
What happens when they are activated?
Salivary Glands: Increased secretion
Acid Secreting cells of Stomach: Increased secretion
