12- CIS CPR Autonomics Flashcards
The Sympathetic nervous system is responsible for producing the fight-or-flight response. Anatomically, it is distinguished by activation of the Presynaptic neurons via __________ nuclei receiving input from brainstem regulatory regions.
Hypothalamic
For the Sympathetics, the NT released from the Presynaptic neuron is…
ACh
For the Sympathetics, what type of receptor is found on the Postsynaptic dendrites/cell body?
Nicotinic Cholinergic Receptors
For Sympathetics, the Postsynaptic axon leaves the Sympathetic chain and travels to the target organ. The NT __________ is released from the Postsynaptic axon.
Norepinephrine
For Sympathetics, the cells of the target organ express what type of receptors?
Alpha-Adrenergic or Beta-Adrenergic Receptors
For Sympathetics, the Presynaptic axons that did NOT synapse with the Sympathetic chain are a special case. They passed through the chain ganglia without synapsing and went to the ________ ________ where they snapped on the _________ cells. The Presynaptic axons released the NT __________ that bound to these cells.
Adrenal Medulla
Chromaffin
ACh
For Sympathetics, the ACh released from Presynaptic axons synapsing with Chromaffin cells bound to what type of receptors on the cells?
Nicotinic Cholinergic Receptors
For Sympathetics, when ACh binds to the Chromaffin cells (via Nicotinic Cholinergic Receptors) there is an influx of ________ into the Chromaffin cells. This produces the release of ________ into the blood.
Sodium
Epinephrine
Alpha- and Beta-Adrenergic Receptors are (IONOTROPIC/METABOTROPIC).
Metabotropic
***Remember, Ionotropic and Metabotropic are both ligand-gated but Ionotropic will change shape and allow ions to pass through a channel when a ligand binds. Metabotropic activates a GPCR when a ligand binds.
Alpha-Adrenergic Receptors have two subtypes, which are…
Alpha1-Adrenergic – Activation on smooth muscle is almost always associated with contraction of the smooth muscle
Alpha2-Adrenergic – On vascular smooth muscle is associated with relaxation/dilation
Beta-Adrenergic Receptors have two important subtypes we talked about, which are…
Beta1-Adrenergic – Found on cardiac myocytes
Beta2-Adrenergic – On smooth muscle and causes relaxation
The Parasympathetic division is often considered to be responsible for “rest and digest”. Once again, brain activation arises largely from the _________, in response to inputs from other parts of the brain including the medulla.
Hypothalamus
For Parasympathetics, the Presynaptic fibers release the NT _________, which binds to _______ _______ receptors on the Postsynaptic dendrites/cell body (which is on or near the target organ).
ACh
Nicotinic Cholinergic
For Parasympathetics, the Postsynaptic fibers release the NT __________ and it binds to _________ _________ receptors on the target organ.
ACh
Muscarinic Cholinergic
Muscarinic receptors have five subtypes, and all are (IONOTROPIC/METABOTROPIC).
Metabotropic
Describe the subtypes of the Muscarinic Receptors.
M1, M3, and M5 = Associated with IP3/DAG production and release of intracellular Calcium stores
M2 and M4 = Associated with Gi proteins and lead to a reduction in cAMP
T/F. The SA Node is strongly innervated by both Sympathetics and Parasympathetics.
True
What provides Parasympathetic innervation to the SA Node?
Vagus N.
What type of Parasympathetic receptors lie on the specialized conducting tissue of the SA Node?
Muscarinic Receptor
What are the actions and effects of the Parasympathetics for the SA Node?
Action = Decreases rate of depolarization of the pacemaker potential
Effect = Slows heart rate
What provides Sympathetic innervation to the SA Node?
Arises from T1-T5 levels of the spinal cord
What type of Sympathetic receptors lie on the target organ, in this case the SA Node?
Beta1-Adrenergic Receptor
What are the actions and effects of the Sympathetics for the SA Node?
Action = Increase the rate of depolarization of the pacemaker potential
Effect = Increases heart rate
What provides Parasympathetic innervation to the AV Node and Ventricular conducting pathways (Bundle of His and Purkinje Fibers)?
Vagus N.