Chapter 33

1. Chapter 33 Anatomy of blood vessels

2. The wall of the blood vessels • Three distinct layers • Tunica intima • Lines the lumen • Simple squamous epithelium • endothelium and endocardium • Tunica media • Smooth muscle, • collagen and elastic fibers • Regulates the diameter of the blood vessels

3. The wall of the blood vessels • Tunica externa or adventitia • Areolar or fibrous connective tissue • Supports the vessel • Protects the vessel

4. The wall of the blood vessels

5. Arteries • Blood vessels that conduct blood away from the heart and toward tissues. In the pulmonary circulation, pulmonary arteries conduct deoxygenated blood to the lungs. In the systemic circulation, the aorta and its branches conduct oxygenated blood toward the systemic tissues

6. Arteries • Small arteries are called arterioles. Arterioles conduct blood into a network of even smaller vessels, or capillaries.

7. Arteries • Subject to pressure fluctuations • Thick walls • Contain more smooth muscle and elastic tissues • Narrower lumen than veins

8. Arteries • Can be classified as: • Elastic • Closer to the heart • Large arteries • More elastic fibers than smooth muscle

9. Arteries • Muscular • Farther from the heart • Smaller arteries • More smooth muscle than elastic fibers

10. Veins • Blood vessels that conduct blood toward the heart. In the pulmonary circulation, the pulmonary veins return oxygenated blood from the lungs. In the systemic circulation the vena cava returns deoxygenated blood from the rest of the systemic loop. Venules are small veins.

11. Veins • Far from the heart • Not subjected to pressure fluctuations • Thin walls • Larger lumen than arteries • Presence of valves • Skeletal muscle pump

12. Veins

13. Arteries and veins

14. Aorta • Ascending aorta – first portion • Aortic arch • Descending aorta – within the thorax • Abdominal aorta – within the abdomen

15. Aorta • Ascending aorta • Right and leftcoronary arteries originate from base of aortic sinus • Aortic arch • Brachiocephalic trunk – first branch • Right common carotid • Right subclavian • Left common carotid – second branch • Left subclavian – third branch

16. Aorta • Descending aorta • Thoracic and abdominal aortas

17. Head and neck • Internal Carotid • External carotid • Vertebral • Basilar– formed by the fusion of the vertebral arteries

18. Head and neck

19. Head and neck • Circle of Willis • Posterior cerebral • Posterior communicating • Middle cerebral • Anterior cerebral • Anterior communicating

20. Circle of Willis

21. Upper limb • Axillary – continuation of the subclavian • Brachial – continuation of the axillary • Ulnar – branch of the brachial • Radial – branch of the brachial

22. Upper limb

23. thoracic and abdominal regions • Intercostals • Celiac trunk – to stomach, spleen, and liver • Superior mesenteric – to the small intestine and proximal large intestine • Suprarenal – to the adrenals • Renal – to the kidneys

24. thoracic and abdominal regions • Gonadals • Testicular • Ovarian • Inferior mesenteric – to the distal large intestine • Common iliac – branches from the inferior end of the abdominal aorta

25. thoracic and abdominal regions

26. Pelvis and lower limbs • Internal iliac – to pelvic structures • External iliac- to the leg • Femoral- to the thigh • Popliteal – to popliteal region • Anterior tibial – to the crural region • Posterior tibial – to the sural region • Fibular – to fibular region

27. Pelvis and lower limbs

28. Chapter 33 PART B

29. Veins – head and neck • Brachiocephalic – into sup.vena cava • Subclavian – lateral branch of brachiocephalic • Internal jugular – medial branch into the brachiocephalic vein • External jugular – external vein of the neck that returns blood to the subclavian

30. Head and neck

31. Head and neck • Sinuses – drain blood from the cranium • Superior sagittal • Inferior sagittal sinus • Transverse

32. Cranium

33. Upper limb and thorax • Axillary – it is a continuation of the subclavian • Basilic – medial and empties into the brachial • Brachial – continuation of axillary • Cephalic – lateral and empties into the axillary • Medial cubital – connects basilic to cephalic

34. Upper limb and thorax • Ulnar • Median • Radial • Azygos – unpaired branch into the sup. Vena cava. Drains the right side of the thorax. • Hemiazygos, and accessory hemiazygos -2 sets of multiple veins that empty into the azygos and drain the left side of the thorax. • Intercostals

35. Upper limb and thorax

36. Abdominal veins • Hepatic • Renal • Gonadal – testicular or ovarian • Right side empties into inf. Vena cava • Left side joins with left renal • Common iliac – two branches that fuse to become inf. Vena cava

37. Hepatic portal system • Portal circulation is a set of vessels that begins and ends with capillary networks. • It returns blood from the digestive system to the liver • From the liver the blood flows to the inf. Vena cava

38. Hepatic portal system • Hepatic portal vein – going to the liver • Liver • Hepatic vein - from the liver to inferior vena cava

39. Hepatic portal system

40. Lower limbs • Internal iliac • External iliac • Femoral • Great saphenous – medial;into the femoral vein. • Popliteal • Small saphenous - lateral and posterior; into the popliteal.

41. Lower limbs • Anterior tibial - branch into the popliteal • Posterior tibial – branch into the popliteal • Fibular

42. Lower limbs

43. Vessels on the Cat Thoracic Cavity and Arm • Arteries • Aorta • Brachiocephalic trunk • Common carotid- right and left • Subclavian – right and left • Axillary • Brachial

44. Vessels on the Cat Thoracic Cavity and Arm • Veins • Brachiocephalic trunks • Jugular –internal and external • Subclavian • Brachial

45. Vessels on the CatAbdominal Cavity and Leg • Arteries • Abdominal aorta • Celiac trunk • Superior mesenteric • Renal • Inferior mesenteric • Iliac – common, external and internal • Femoral

46. Vessels on the Cat Abdominal Cavity and Leg • Veins • Inferior vena cava • Hepatic portal vein • Renal • Iliac – common, internal and external • Great saphenous • Femoral