1. Circulatory System Blood Circulatory System -arterial system -capillaries -venous system Lymphatic System -capillaries and ducts -lymphatic organs spleen, tonsils, thymus, lymph nodes

2. Arteries* and Veins: Three layers tunica intima squamous epithelium basal lamina subendothelial layer * internal elastic membrane tunica media smooth muscle * external elastic membrane tunica adventitia connective tissue vasa vasorum nervi vascularis

3. Arteries elastic arteries (large :aorta, pulmonary vein) reduced internal elastic membrane tunica media- elastic fibers, smooth muscle muscular arteries (medium) prominent internal elastic membrane tunica media:>smooth muscle <elastic fibers small arteries/ arterioles classified by # smooth muscle layers arterioles 1-2; small artery 3-8 precapillary sphincter- smooth muscle

4. Aorta Medium artery arteriole

5. Venous System Large veins: 3 layers not distinct lumen larger than artery lumen often collapsed valves Medium veins: similar to large vein structure adventenia thicker than media several layers of muscle Venules: postcapillary- fluid/cell loss - histamine muscular: 1-2 layers of muscle

6. Vein Artery Vein 3 layers not as distinct lumen larger than artery lumen often collapsed valves

7. Vein and valve venul e arteriole capillary Medium artery vein

8. Capillaries - simple squamous epithelium - no smooth muscle - basal lamina (basement membrane) - pericytes within basal lamina - large surface area for exchange - primary site of exchange for fluid electrolytes, gases, and macromolecules

9. Capillary Bed

10. Capillaries Types: continuous fenestrated discontinuous (sinusoidal)

11. Continuous Capillaries - close cellular interconnections junctional complexes - permeable to small molecules <10nm in diameter - most transport via pinocytotic vesicles - muscle, skin, lungs, adipose tissue, CNS*, retina and mammary glands

14. Transcellular Transport - pinocytotic vesicles Junctional Complex - zonula occludens - zonula adherens - desmosome apical basal

15. Pericyte: undifferentiated cell with multiple processes give rise to new endothelial cells contained within basal lamina

16. Fenestrated Capillaries - contain 'windows’, fenestrations - easy passage of larger molecules (10-100nm) - number of fenestrations varies with absorption - pinocytotic vesicles - diaphragms -nonmembranous - basal lamina intact - kidneys, pancreas, gallbladder, intestine

19. Continuous capillary Fenestrated capillary

20. Discontinuous (sinusoidal) Capillaries - large diameter - wide gaps between cells - relatively free movement (even cells) - gaps or missing basal lamina - liver, spleen, ovaries, some endocrine glands

21. PERMEABILITY Low High Extremely High

22. Blood flow through Capillary Bed -controlled by precapillary sphincters -smooth muscle band at arteriole/capillary fajerpc.magnet.fsu.edu/.../ 30_Circulatory.htm

23. Fluid Movement across Capillary Wall: Starling’s Law of Capillaries - Governed by Hydrostatic and Osmotic Pressures Capillary Hydrostatic Pressure (HP): blood pressure forces fluid OUT Osmotic Pressure (OP): pressure due to plasma proteins trapped in capillary draws fluid IN

24. HP > OP -->fluid moves from cap to tissue--> FILTRATION occurs at arteriole end of capillary HP fluid moves from tissue to cap-> REABSORPTION occurs at venous end of capillary SMALL NET LOSS OF FLUID FROM BLOOD

25. Residual Fluid is taken up by Lymphatic Capillaries -lymphatic ducts -returned to blood

26. Lymphatic Capillaries and Vessels -blind end capillaries -interstitial fluid pressure drives lymph into lymph capillary

27. Lymphatic Capillaries and Vessels - one cell thick: overlapping pattern– shingles - one-way valves ensure flow away from tissues

28. Lymphatic Capillaries and Vessels - one cell thick: overlapping pattern– shingles - one-way valves ensure flow away from tissues

29. Lymphatic Capillaries and Vessels

30. The flow of lymph is regulated by: 1. Skeletal Muscle Pump. 2. Respiratory Pump. 3. Contraction of smooth muscle in larger lymphatic vessels walls 4. Pressure on lymphatic vessels by expansion/recoil of nearby arteries Skeletal muscle pump www.cvphysiology.com/ Cardiac%20Function/CF018.htm

31. A. A 62 year old woman has marked swelling of ankles and lower legs. Form a hypothesis stating what you think could account for this symptom. B. Design an experiment that will test your hypothesis.

32. Edema: accumulation of fluid in interstitial spaces Hypotheses: 1.Increased capillary hydrostatic pressure - gravitational forces - in heart failure 2.Decreased osmotic pressure - loss of plasma proteins from kidney or liver disease 3.Increased capillary permeability - inflammatory compounds- histamine, Anaphylaxis - trauma- burns 4.Lymphatic obstruction (as occurs in filariasis) - side effect of surgery - Elephantiasis (filariasis)

33. Lymphatic filariasis (elephantiasis) - caused by parasitic worm, Wuchereria bancrofti - transmitted to humans by mosquitoe bites - painful, disfiguring chronic enlargement of arms, legs and genitals

34. Lymphangiogram Visualization of lymph system of legs Inject dye between toes, visualize lymph vessel Inject dye directly into lymph vessel Image dye-stained lymphatic system Capillary Permeability Inject tracers of variable sizes Identify location within and outside vessels

35. Lymphatic System - monitor body surfaces and internal fluids - react to potentially harmful substances

36. Lymphatic Tissues - Concentrated near respiratory tract digestive tract reproductive tract

37. Antigen: foreign substance First Encounter->Nonspecific Inflammatory Response Mast cells -Histamine release -Vasodilation -Increase permeability Neutrophils -enzymatic digestion of virus Macrophages -cytokine release -phagocytosis -antigen presentation