blood vessels and lymphatics *not diagram heavy

the glycocalyx layer on endothelial cells plays a crucial role in the regulation of fluid exchange in capillaries. How does the glycocalyx influence the starling forces involved in capillary fluid dynamics?

it prevents large proteins from exiting the bloodstream, maintaining capillary oncotic pressure and reducing fluid loss

artery

a blood vessel that carries blood away from the heart, where is branches into small vessels

arterioles

smallest arteries that further brach into tiny capillaries where nutrients and waste are exchanged

what is the pathway from artery to vein?

1. artery

2. arterioles

3. capillaries

4. vein

what is the general appearance of an artery?

• thick walls with small lumens

• appear rounded

what is the general appearance of a vein?

• thin walls will large lumens

• appear flattened

what is layer 1?

tunica externa

what is layer 2?

tunica media

what is layer 3?

tunica intima

describe the tunica intima of arteries

• endothelium will appear wavy from constriction of smooth muscle

• internal elastic membrane (large vessels)

what is the innermost layer of the tunicas in blood vessels?

tunica intima

what is the middle layer of the tunica in blood vessels?

tunica media

what is the outermost layer of the tunica in blood vessels?

tunica externa

describe the tunica interna in veins

• endothelium appears smooth

• internal elastic membrane ABSENT

what is normally the thickest layer of the arteries?

tunica media

what is normally thinner than the tunica media besides in large arteries?

tunica externa

what cells dominate in tunica media of arteries?

smooth muscle cells and elastic fibers

what does the proportion of cells depend on in the tunica media of the artery?

vary with distance from heart

what is the thickest layer of tunica in veins?

tunica externa

what cells dominate in tunica media of veins?

smooth muscle cells and collagen fibers

what is present in the tunica media of veins?

• nervi vasorum

• vasa casorum

what is absent in the tunica media of veins?

external elastic membrane

what is the composition of the tunica externa in arteries?

collagenous and elastic fibers

what is present in the tunica externa of arteries?

• nervi vasorum

• vasa vasorum

what cells dominate in tunica externa of veins?

• dominate: collagenous and smooth fibers

• present: smooth muscle fibers (some)

what is present in the tunica externa of veins?

• nervi vasorum

• vasa vasorum

why is it good that we have thick smooth muscle in arteries?

controls pressure of blood flow

what are structures 1 and 2 in the slide?

1. artery

2. vein

what are the tributaries of hepatic portal vein?

1. cranial mesentaric vein

2. celiac vein

3. caudal mesenteric vein

what does swelling of the lymph nodes indicate?

presence of infection in the drainage area

what lymph nodes do you palpate in a routine clinical examination?

superficial lymph nodes

what is 1?

superficial inguinal node

what is 2?

iliac node

what is 3?

submandibular node

what is 4?

retropharyngeal node

what is 5?

facial node

what is 6?

prescapular (superficial cervical) node

what is 7?

axillary node

what is 8?

femoral node

what is 9?

popliteal node

is the tracheal duct/trunk paired or unpaired?

paired

is the thoracic duct/trunk paired or unpaired?

unpaired

where is the tracheal duct/trunk located?

in the neck, on both sides of the trachea

what structure is the tracheal duct/trunk located within?

carotid sheath

what structure does all lymph from the body drain into?

left external jugular vein

where is the cranial part of the thoracic duct located?

the left side around the 5/6th thoracic vertebra

what does the thoracic duct open into?

left external jugular vein/cranial vena cava

what is the black arrow pointing to? (blue line)

thoracic duct

what does the pink line represent?

left thoracic duct

what does the green line represent?

right thoracic duct

what are the vascular components of the lymphatic system?

1. lumbar trunks

2. cisterna chyli

3. thoracic duct

4. tracheal ducts/trunks

what is the lympho-center in the horse?

rather than having one large lymph node, horses have an collection of several smaller lymph nodes

list the flow of lymph in order

1. organ

2. lymph node

3. other lymph node

4. venous system

5. cranial vena cava or left jugular vein

what is the flow of lymph?

UNIDIRECTIONAL FLOW

afferent lymphatic vessels

carry lymph into the lymph node

efferent lymphatic vessels

carry lymph away from the lymph node

where does the tracheal trunk bring lymph from?

brings lymph from head, neck, and forelimb before joining thoracic duct

what is the flow of lymph from lumbar trunk?

1. lumbar trunk collects lymph from the lower limbs and pelvis

2. transported chyle cistern

3. drained into the thoracic duct

what are the superficial veins used for venipuncture?

1. cephalic vein

2. femoral vein

3. saphenous vein

4. external jugular vein

5. coccygeal vein

lymphatic system components

1. vascular component

2. lymph nodes

3. lymph organs

In studies on canine gastric perfusion, how could the use of NSAID affect endothelial function in stomach?

it impairs the production of prostaglandins, which can reduce mucosal blood flow and increase susceptibility to gastric lesions

what is the correct sequence of the blood flow in systemic circulation?

1. heart

2. body

3. heart

blood from which organs is drained by the hepatic portal vein?

1. stomach

2. intestines

3. pancreas

4. spleen

which additional veins, via portal circulation, provide blood to the avian kidney?

external iliac and ischiatic vein

what is there more of in the limbs of animals: veins or arteries?

veins

what is not present in the forelimb?

there is no cephalic artery, they have superficial veins

what vein converges to form the caudal vena cava?

common iliac veins

what are the tributaries of the common iliac vein?

1. deep circumflex iliac vein

2. gonadal vein

3. renal vein

4. phrenicoabdominal vein

5. hepatic vein

external and internal veins are…

tributaries of the common iliac veins

deep circumflex iliac vein

• paired

• location: parietal

gonadal vein

• paired

• visceral

what does the left gonadal vein open into?

renal vein

renal vein

• paired

• location: visceral

phrenicoabdominal vein

• paired

• location: parietal

where will the blood of the GI tract travel?

1. liver

2. caudal vena cava

what tributary of the vena cava will not be present in venous return and why?

cranial mesentaric artery since they go to liver

adventitia

the outermost layer of the blood vessel that provides support and anchors vessel to surrounding tissue

what is the composition of the adventitia?

1. connective tissue

2. cells

3. extracellular matrix

what type of connective tissue makes up adventitia?

loose and dense irregular connective tissue with collagen and elastin fibers

what is the function of the connective tissue in the. adventitia?

anchor vessel to surrounding tissues

what cells are present in the adventitia?

• fibroblasts

• macrophages

• stem cells

• myofibroblasts

• pericytes

what is the composition of the extracellular matrix of the adventitia?

rich in proteoglycans and glycosaminoglycans

what is the purpose of the extracellular matrix of the adventitia?

contributes to structural integrity and flexibility of the vessel wall

vasa vasorum

contain tiny blood vessels present in the adventitia that supply larger vessels to supply oxygen and nutrients to outer portion of vessel wall

what else does the vasa vasorum contain besides tiny blood vessels?

lymphatic vessels to help drain excess fluid from vessel wall

Defense and hemodynamic

nervi vasorum

are small nerves present in the adventitia that regulate smooth muscle contraction influencing vasomotor controland sensory functions of blood vessels

function of large elastic arteries

steady blood flow

function of median muscular arteries

distribution

function of smaller arteries or arterioles

resistance and pressure

function of small veins or venules

draining

function of medium veins

unidirectionality and venous return

function of large veins

veinous return

do veins or arteries flow away from the capillary beds?

veins

do veins or arteries flow towards the capillary beds?

arteries

what are the different portal systems of systemic circulation in the body?

1. hepatic portal system

2. pituitary hypothalmic system

3. renal portal system

4. adrenal glands portal system

in which species is the renal portal system present?

birds and reptiles

what is the pathway for pulmonary circulation?

1. right ventricle

2. main pulmonary artery

3. lungs

4. pulmonary vein

5. left atrium of heart

what is the pathway for systemic circulation?

1. left ventricle

2. aorta

3. body tissues

4. superior and inferior vena cavae

5. right atrium of heart

what structure in the heart is responsible for collecting deoxygenated blood from organs?

1. cranial vena cava

2. caudal vena cava

3. azygous vein

renal veins

return of deoxygenated filtered blood (kidney used the oxygenated blood!)