Anatomy HSF II Lecture III Flashcards
Somatic Innervation
Concerns innervation of body wall, like skin and skeletal muscle
Visceral Innervation
Concerns Internal Organs. Example Heart
Functional dichotomy of Nervous System: Body Wall
Somatic Sensory and Somatic Motor
Functional Dichotomy of Nervous System: Internal Organ
Visceral Sensory and Visceral Motor (synonomus witih autonomic)
What are target tissues for visceral motor innervation
Smooth Muscle, Cardiac Muscle and Gland. Under Unconscious control.
Is Visceral Innervation a two or one neuron pathway
Two neurons connect the CNS to Target Tissue.
Is Visceral Innervation a two or one neuron pathway
Two neurons connect the CNS to Target Tissue.
Somatic Innervation
Concerns innervation of body wall, like skin and skeletal muscle
What are components of Visceral Motor Innervation?
Sympathetic Innervation and Parasympathetic Innervation
What are increases in sympathetic innervation usually associated with
Energy Expenditure and increased metabolic Rate
What is constricted during sympathetic innervation of visceral organs
Pulmonary Arteries
Where is blood flow decreased during sympathetic response
Digestive Organs
What uses a 2 neuron pathway
Both Sympathetic and Parasympathetic Visceral Innervations.
Where is the cell body of Neuron in a visceral innervation
In the CNS somewhere
Where is the ganglion for a 2 neuron system
in the organ or body somewhere
Where is the preganglyonic cell body for sympathetics
T1- L2 levels of spinal cord only. (thoracolumbar distribution)
Where are the pre-ganglyonic cell body distributions for parasympathetics
S2-S4 or the brain
What are the pre and post ganglionic neurons like in Sympathetic innervation
Pre-Ganglyonic is usually shorter. Post Ganglyonic is Long
What are Pre- and Post ganglyonic neuron like for parasympathetic innervation
Preganglyonic: Long. Post ganglyonic; Usually located in the target organ. So for parasympathetic the entire nerve will be preganglyonic
What is never used in Organ Innervation?
Grey Ramus Communicantes
Nerve Pathway for above the Diaphgram Sympathetic.
Preganglyonic cell body in lateral horn > Spinal Nerve Root Proper > White Ramus Communicantes (Synapse) > Thoracic Splanchlic Nerve (Post ganglyonic axon) > thoracic organ
Sympathetic Pathway to abdominal organ
Lateral Horn > Spinal Nerve Proper > White Ramus Communicantes (No synapse) > Organ > Post ganglyonic on the organ. (Abdominal Splanchlic Nerve)
What are plexuses associated with in Thorax?
Organs
What are plexuses associated with in Abdomen
Blood vessels
Where does parasympathetic innervation come from for thorax organs
Vagus Nerve
Where does parasympathetic innervation come from for abdominal organ
Vagus Nerve (CN X). Pelvis and lower abdomen from Sacral Nerves S2-S4
Where are parasympathetic post ganglyonic cell bodies located
Directly on walls of Organs.
Does spinal cord injury impact parasympathetic
No because it bypasses the spinal cord. Comes directly from brain
What are the splanchlic nerves in Pelvis? (symp or para)
Parasympathetic
Path of Lower pelvic innervation
Lateral Horn > Ventral Root > Spinal Nerve Proper > Ventral Ramus > Organ. Called Pelvic Splanchlic Nerve
How is visceral Pain and Visceral Afferent Different?
Visceral afferents are sensory other than pain. They have different path and perception differenc
Define Visceral Pain
Dull, duffused and poorly localized. You can identify the quadrant the pain is coming from but not exact location
Some things that can cause viscearl pain
Ischemia, prolonged muscle contraction, muscle cramping and stretching. Cutting tearing temp won’t have any impact on visceral pain receptors
Visceral Pain pathway Thorax and Abdomen
They follow sympathetic pathway backwards all the way to spinal nerve proper. Then they pass through dorsal root like sensory gangli. Their cell body is found in Dorsal Root Ganglia
What pathways to visceral Pain for Pelvis follow
They follow parasympathetic pathways. Cel bodies found in dorsal root ganglia
What kind of neuron pathway is sensory?
One Neuron Pathway. Passes through sympathetic ganglia without doing anything
For parasympathetic is there a synapse in dorsal root ganglion
NO
Visceral Afferents
Most aren’t percieved conciously. They regulate autonomi processes
What carriers visceral afferent for thorax and upper abdomen?
Vagus Nerve
What carrier visceral afferent for lower abdomen and pelvis
Pelvic Splanchlic Nerve
What is special about Vagus Sensory
It is the only sensory that has nothing to od with dorsal root ganglia. It passes through Vagal Ganglia
Referred Pain
Pain in Visceral Organ triggers pain at the dermatome in skin. Dermatome that belongs to same spinal cord level as the nerve that innervates impacted organ
Mechanism for referred pain
May involve crossing of signals in dorsal horn
