Intro to Lymphatics and Autonomics Flashcards
Functions of Lymphatic System
- Drain excess extracellular fluid from body and return it to the veins of the circulatory system
- Mounts immune responses in body
- Absorbs lipids from digestive tract
What is in lymph?
Interstitlal fluid and WBC’s, similar to plasma
Role of Lymph Nodes and What They Contain
Presence of infection?
Filter Lymph
Contain B and T cells (lymphocytes)
Can be enlarge in presence of infection
Primary Lymph Organs
Produce and mature lymphocytes (T and B cells)
Thymus and bone marrow
Secondary Lympohoid Organs
- Store lymphoctes and initiate adaptive immune responses
- Lymph nodes, spleen, lymphoid nodules in GI tract, tonsils
Structure of Lymphatic Vessels
- similar structure to blood vessels: tunica intima, tunica media, tunica adventitia
- Have valves to prevent backflow like veins
Structure of Lymphatic Capillaries
are like cardoivascular cappillaries and have only a monolayer of endothelium
Afferent Lymphatic Vessels
Drain from capillary beds towards lymph node
Found only with lymph nodes
Efferent Lymphatic Vessels
Drain away from lymph node towards venous system
Found with nodes and in the spleen and thymus
Flow of Lymphatic System
- Lymph vessels collect extracellular fluid in capillary beds
- Lymph flows to nodes via afferent vessels
- Lymph is filtered in nodes
- Lymph flows towards venous system via efferent vessels
- Lymph is returned to circulatory system at the subclavian veins
Right Lymphatic Ducts Drain Into:
Right subclacian vein
Left jugular trunk drains to
Left thoracic duct
Thoracic duct drains
at the junction of the L. subclavian and left internal jugular v.
drains left side of neck, head, thorax; left upper limb and all of abdomen and lower limbs into left subcalvian vien
Cisterna Chyli
dilation at the inferior end of the thoracic duct, receives lymph from abdomen, pelvis and lower limbs
Right upper limb drains through
small symphatic trunks to right subclavian vein
Oral cavity drains to
to parotid, submandibular, submental and superior DCLN nodes
S3P DCLN
Deep cervical lymph nodes drain
lymph from head and neck, either directly or indirectly through other nodes
Deep cervical lymph nodes found
along internal jugular vein and inside carotid sheath
Superior DCLN drains
face, oral cavity, anterior neck
Inferior DCLN drains
Drains posterior scalp and neck
Jugular trunk (left and right)
Superior and inferior DCLN efferent vessels join to form the jugular trunk
Left: drains the thoracic duct
Right: Drains to venous angle of subclavian and internal jugular veins
Sentinel node
First node biopsied to determine tumor stage
Signal node (of Virchow)
Nodes that surround thoracic duct in left supraclavicular fossa
indicative of metastasis of abdominal cancer
After entering the venous system, where do cancer cells metastasize to?
Brain, bone, lung and liver
Functions of Sympathetic Nervous System
“Fight or Flight”
Dilates pupils
controls arterial constriction and dilation in periphery
dilates bronchi
initiates ejaculation
Sympathetic Nervous System: Thoracolumbar System
Pre-synaptic neuron has cell body in lateral horn of T1-L2 spinal levels
axon in white ramus communicans
post-synaptic neuron has cell body in sympathetic chain ganglion (paravertebral ganglion) or in a pre-vertabral ganglion (GI tract only)
Axons travel with other nerves to their target
White Ramus Comminicans
Contains the axon of pre-ganglionic sympathtic neurons headed towards the sympathetic chain
Grey Ramus Communicans
Contains the axons of post-ganglionic sympathetic neurons headed towards their target organ
Sympathetic Chain/Splanchnic Nerve
Not all sympthatetic neurons synapse at the chain ganglion corresponding to their spinal level –> some ascend through the sympathetic chain to reach the head and neck
The connection between ganglia is called the sympathetic chain and is found in the thorax and neck
Nerves will also descend to reach the abdomen and pelvis –> splanchnic nerves
Cervical Sympathetic Chain Composed of
- Sympathetic axons
- Pre-synaptoc neurons have cell bodies in upper thoracic spinal levels (T1-T4)
- Targets of neurons in servical chain: head, neck and heart
Cervical Chain Ganglia:
(superior/middle/inferior)
- SN cell bodies
- Superior: Found at C2/C3 vertabrae
- Middle: Found at C6 vertabrae
- Inferior: Found at C7 vertabrae
- Sometimes fuses with the T1 ganglion to form the stallate ganglion
SN to Head
Presynaptic cells bodies in T1-T4
Ascend in cervical sympathetic chain
synapse in superior cervical ganglion
Post-synaptic axons travel to head in carotid plexus
SN to Neck
Presynaptic cell bodies in T1-T4
ascend in cervical sympathetic chain
Synapse in inferior and middle cervical ganglia
Post-synaptic axons travel to target on other nerves
SN to Heart
Presynaptic cell bodies to T1-T6
ascend in cervical sympathetic chain
synapse in superior, middle and inferior cervical ganglia
post-synaptic axons descend to heat as cardiac nerves
Horner’s syndrome (causes and symptoms)
- disruption of sympathetic nerves to head
- causes
- damage to sympathetic chain
- damage to pre-ganglionic neurons in spinal cord
- symptons
- ptosis (drooping eyelid)
- miosis (constricted pupil)
- anhidrosis (decreased sweating) on face
Parasympathetic Nervous System Functions
- Constricts pupils
- decreases cardiac and respiratory rates
- constricts bronchi
- stimulates digestion
- relaxes urethral sphincter
- initiates arousal and erection
Parasympathetic Nervous System: Craniosacral System-Cranial Components
to head, neck, thorax, and most of GI tract
- Pre-synaptic neuron: cell body in brainstem nuclei of CN III, VII, IX, and X
- Post-Synaptic neuron has cell body in cranial ganglia (head and neck) or in intramural ganglion (in wall of target organ)
- Axons travel with other nerves to their target
Parasympathetic Nervous System: Craniosacral System-Sacral Component
to hindgut and pelvis
- pre-synaptic neuron has cell body in laternal horn of S1-S3 spinal levels
- Post-synaptic neuron has cell body intramural ganglion (wall of target organ)
Parasympathetic nerves of head and neck are carried by cranial nerves:
- CN III: oculomotor nerve
- CN VII: facial nerve
- CN IX: glossopharyngeal nerve
- CN X: vagus nerve
- all PN to neck and thorax carried by CN X
