Autonomic Nervous System Flashcards
What are the components of the CNS? The PNS? What are the different types of nerves that are part of the PNS?
What do somatic efferent nerves do? What about visceral efferent nerves?
What do somatic afferent nerves do? What about visceral afferent nerves?
Which of the afferent/ efferent nerves are part of the somatic nervous system?
Which of the afferent/ efferent nerves are part of the autonomic nervous system?
What are visceral efferent and afferent nerves responsible for?
Visceral efferent and afferent axons are part of the autonomic nervous system responsible for involuntary control of smooth muscle, cardiac muscle, some glands and physiological life support functions (e.g., heart rate, blood pressure, digestion)
What does the somatic nervous system innervate? How many neurons does it have/ how is it structured?
What does the autonomic nervous system innervate? How many neurons does it have/ how is it structured?
True or False: Somatic nervous system has non myelinated axons.
FALSE
Does the autonomic nervous system have myelinated axons?
What systems does the autonomic nervous system regulate?
True or False:Changes in the level of afferent and efferent activity in sympathetic and parasympathetic nerves occur primarily independent of conscious or voluntary control.
TRUE
What are the components of the general visceral efferent (GVE)
- PNS, SNS, enteric nervous system
How many subdivisions are there for the Peripheral ANS? What are they based on?
The peripheral ANS is divided into two major subdivision (SNS)
based on the origin of their preganglionic neurons and on their synaptic transmitters at the target organ
True or False: All of the parts of the PANS originate in the CNS.
FALSE: The peripheral ANS has two subdivisions that originate in the CNS and one that does not
Sympathetic nerves have ____ preganglionic neurons and ____ postganglionic axons.
Short preganglionic and long postganglionic axons
How do preganglionic axons of the SNS leave the spine? Where do they enter?
- Preganglionic axons leave the spinal cord by way of the first thoracic through the third or fourth
lumbar spinal nerves. - The preganglionic axons pass through the ventral root and then to enter the paravertebral
sympathetic ganglion chain, the sympathetic trunk
Paraympathetic nerves have ____ preganglionic neurons and ____ postganglionic axons.
Long preganglionic and short postganglionic axons
Where do parasympathetic nerves originate from? How do preganglionic axons leave the CNS. Where do the preganglionic axons synapse?
- Parasympathetic nerves originate from cell bodies in the brainstem and sacral sections of the
spinal cord - Long preganglionic and short postganglionic axons
- The preganglionic axons leave the CNS by way of cranial nerves III (oculomotor), VII (facial),
IX (glossopharyngeal) and X (vagus) and several sacral spinal nerves - Preganglionic axons synapse in diffuse parasympathetic ganglia residing close to or within
(intramural ganglia), pelvic viscera
The enteric nervous system is….
Does it function independently or dependently on the CNS?
The enteric nervous system is an extensive network of interconnected sensory and motor interneurons
within the gastrointestinal wall that can control gut function independently of the CNS. However, its sensory and motor interneurons can also be influenced by the CNS through input from sympathetic
and parasympathetic subdivisions
What are the components of the enteric nervous system? What is it innervated by?
its characterized by the presence of a complex intrinsic neural network that includes the myenteric
plexus and the submucosal plexus
* Is extensively innervated by nonadrenergic-noncholinergic (NANC) nerve fibers
What has Dual ANS innervation? What is that?
Many organs and tissues are innervated by both sympathetic and parasympathetic arms of the ANS, dual ANS innervation (e.g., heart and urinary bladder)
SNS and PNS
True or false: In many instances physiologic responses produced by parasympathetic or sympathetic nerves to target tissue/ organ with dual innervation is usually functionally synergistic.
FALSE: In many instances physiological responses produced by activation of parasympathetic or sympathetic nerves to the target tissue or organ that receives dual ANS innervation are functionally antagonistic
If there is dual ANS innervation witll there be equal function/ balance function?
The presence of a dual ASN innervation does not indicate that the physiological function of that target is balanced to the same degree for each arm of the ANS. The basal physiological function of many organs is weighted towards either PSNS or SNS regulation
What organs only have sympathetic innervation?
Organs with only sympathetic innervation
* Adrenal medulla
* Peripheral blood vessels
* Pilomotor muscles
* Sweat glands
What is the adrenal medulla? What are chromaffin cells? What are they innervated by? What receptors are found here? What is synthesized/ released by chromaffin cells?
What is the primary neurtransmitter released from preganglionic neurons at sympathetic ganglionic sites? What receptor does it primarily bind to? What are the nerve fibers called that synthesize/ release ach? What are postganglionic cholinergic fibers? What receptors do they bind to?
What is the predominant neurotransmitter released from postganglionic SNS Neurons? What receptors does it bind? What are the nerve fibers called that synthesize/ release this neurotransmitter? What is another neurotransmitter that is released by soe postganglionic SNS neurons? What is it related to? What is it important for/ What does it bind to?
What is the predominant neurotransmitter released from preganglionic PNS Neurons? What receptors does it bind? What do the postganglionic PSNS neurons arise from? What is the primary neurotransmitter released from PSNS postganglionic neurons?
What does it bind to/ activate?
What are the Non-adrenergic and Non-cholinergic Neurotransmitters (NANC)?
- Adenosine triphosphate (ATP)
- Vasoactive Intestinal polypeptide (VIP)
- Neuropeptide Y (NPY)
- Serotonin (5-HT)
- Substance P
- Calcitonin gene-related peptide (CGRP)
- Nitric Oxide (NO)
Many of the same molecules/substances identified as _________ in ANS nerves also play a role as ________ released from NANC nerve endings
Many of the same molecules/substances identified as cotransmitters in ANS nerves also play a role as neurotransmitter released from NANC nerve endings
Where are cotransmitter molecules released from? What may be stored with ATP in the same vesicle and released together?
Cotransmitter molecules are released from many posganglionic fibers at target tissues
NE
What activates purinergic receptors? What are they identified as?
ATP mediates responses via activation of purinergic receptors that are identified as adenosine
P1 receptors and P2X and P2Y receptors
What is another NANC that is released with NE from sympathetic nerves? What is its function at neurokinin receptors Y1 and Y2? What is its role in sympathtic pre and postsynaptic sites?
Neuropeptide Y (NPY) can also be released with NE from sympathetic nerves. It is an agonist at
neurokinin receptors, Y 1 and Y2 .
NPY has the physiological role to modulate sympathetic
neurotransmission at both pre and postsynaptic sites.
What is released along with Ach from many postganglionic PSNS fibers at target tissues/ organs?
Cotransmitters are released along with Ach from many postganglionic PSNS fibers at target tissues
and organs
Parasympathetic nerves innervating the urinary bladder release ________ as a cotransmitter
ATP
Parasympathetic nerves innervating the salivary glands utilize _____________
as a cotransmitter
vasoactive intestinal polypeptide (VIP)
True or False: Cotransmitters have an important signaling role in the cardiovascular, urogenital, and respiratoy systems increasing pharmacological and physiological finesse in the regulation of tissue responses
True
What are the vesicle types that can be found at cholinergic nerve terminals?
Cholinergic nerve terminal contain several types of vesicles:
* Small membrane bound vesicles where ACh can be stored
* Large vesicles that contain biological substances