CV Histology

Question 1

What are the three layers of an artery?

Answer 1

Intima, media, adventitia

Question 2

What does the intima include?

Answer 2

Endothelium, basal lamina, myointimal cells (sm muscle, produce collgen, can phagocytose)

Question 3

What are the functions of endothelium?

Answer 3

Barrier: tight junctions
Filter/transport
Secretion: vasodilation/vasoconstriction
Cell growth
Clotting: inhibit/promote
Lipoprotein metabolism (LDL, VLDL)
Produce ECM
Immunologic

Question 4

What does the media include?

Answer 4

Elastic fibers, smooth muscles cells (make collagen, elastin, proteoglycans), innervation (adrenergic=constriction, cholinergic= dilation, afferent for pressure/CO2)

Question 5

What does the adventitia include?

Answer 5

Connective tissue, vasa vasorum= vessels that supply the media

Question 6

What are the layers of the heart?

Answer 6

Epicardium = mesothelium, epicardial fat, then myocardium

Myocardium = myocytes

Endocardium= inside of heart

Question 7

What is the constitution of the myocardium?

Answer 7

Myocytes = contract
Myocytes secrete BNP when stretched (atrial cells)– helps kidney secrete water, biomarker of heart failure
Myocytes also involved in conduction
Nerves
Connective tissue
Vessels
Leukocytes

Question 8

What type of cells is the conduction system of the heart made from?

Answer 8

Specialized myocytes that don’t contract, they conduct

Question 9

What is the endocardium made from?

Answer 9

Collagen, elastic fibers, smooth muscle cells, endothelium

Question 10

What determines the thickness of endocardium?

Answer 10

Thickness determined by pressure and turbulence

Question 11

What are the layers of valves?

Answer 11

Spongiosa = looser, connective tissue

Fibrosa = denser connective tissue

Covered by endothelium

Normally don’t have vessels - sign of pathology