Reticuloendothelial system Flashcards
What is the function of the reticuloendothelial system? (RES)
Phagocytosis of pathogens
What are the main components of RES?
Thymus (in childhood) Lymph nodes Spleen Mucosa-associated lymphoid tissue (MALT) Gut-associated lymphoid tissue (GALT) Specialised fixed phagocytes
What are the specialised fixed phagocytes?
Kupffer cells (liver)
Langerhans/dendritic cells (skin)
Dust cells/alveolar macrphages (alveoli)
Microglial cells (brain)
How are Arteries organised?
Lumen, (Vascular endothelium, Subendothelial layer, Internal elastic layer) Intima, (smooth muscle, External elastic membrane) Media, Adventitia
How are Veins organised?
Lumen, Valve cusp, (Vascular endothelium, internal elastic layer) Intima, (smooth muscle) Media, Adventitia
How is blood flow to an area controlled?
Contraction of the arterioles
How can capillaries be organised?
Continuous - no gaps in wall or basement membrane
Fenestrated - Gaps in wall but basement membrane is continuous
Sinusoidal - gaps in both wall and basement membrane
What are the main lymph nodes and where are they located?
Pericranial ring - base of head
Cervical nodes - Along internal jugular vein
Trachael nodes - along the trachea/bronchi
Axilliary nodes - in the armpits
Deep nodes - Along the aorta, celiac trunk and superior and inferior mesenteric arteries
Inguinal nodes - along inguinal ligament
Femoral nodes - along femoral vein
What is the difference beween lymph and Chyle?
Lymph is clear, Chyle is opaque and milky
How does the lymphatic system drain into the blood stream?
Lymph from the head, upper right limb and right throax drain into the right lymphatic duct and into the right venous angle (between the right subclavian vein and right internal jugular vein)
Lymph from the rest of the body drains into the thoracic duct and into the left venous angle (between the left subclavian vein and the left internal jugular vein)
Lymph from the lower half of the body drains into the cisterna chyli before the thoracic duct
What is the function of lymph nodes?
Centres for maturation of B cells and T cells (occurs in folicles)
What is the structure of a lymph node?
Medulla (center), Cortex (Exterior), Capsule (external layer), Subcapsular sinus (macrophages), Folicles, Rich blood supply
What happens to lymph nodes in pathology?
Swelling, palpable
What are the risks of having slow flow of lymph through the system?
Frequent 2ndary tumour growth within lymph nodes
Which lymph nodes are associated with specific cancers/other diseases?
Lateral aortic nodes - Testicular cancer
Axilliary nodes - Breast cancer
Superficial inginal nodes - genital herpes
Cervical lymph nodes - Bronchitis
