HISTOLOGY OF THE VESSELS Dr Altdorfer HISTOLOGY OF

HISTOLOGY OF THE VESSELS Dr. Altdorfer

HISTOLOGY OF THE VESSELS 1) Blood vessels 2) Lymph vessels

Definitions: 1) Artery: 2) Vein:

Arteries - higher pressure thicker walls, smaller lumen than accompanying veins. Three concentric layers: tunica intima - tunica media (capillaries) (arteries!) - tunica adventitia (veins!)

+Vasa vasorum, nerves (max. 5

+Vasa vasorum, nerves (max. 5 +Vasa vasorum, nerves

Elastic arteries Muscular arteries Arterioles Capillaries Venules Medium-sized veins Large veins

Elastic arteries Muscular arteries Arterioles Capillaries Venules Medium-sized veins Large veins Windkessel function

+ vasa vasorum

Atherosclerotioc plaque with haemorrhage

Elastic arteries Muscular arteries Arterioles Capillaries Venules Medium-sized veins Large veins

+Vasa vasorum, nerves (max. 5

Medium sized vessels A V

End arteries

Elastic arteries Muscular arteries Arterioles Capillaries Venules Medium-sized veins Large veins Resistance vessels, sphincter vessels

+Vasa vasorum, nerves (max. 5

Arteriole

Precapillary arteriole

Exchange vessels Elastic arteries Muscular arteries Arterioles Capillaries Venules Medium-sized veins Large veins

+Vasa vasorum, nerves (max. 5

Capillary functions: exchange (diffusion; pinocytosis - transcytosis) secretion -endothelin – 1. -nitric oxide (NO = EDRF) -conn. tissue elements, etc.

e. g. in muscles Fluid exchange e. g. : small intestine (resorption), endokrine glands, kidney Sinusoid: wide lumen Liver, spleen, endokrine glands, lymph node Hepatic sinusoid liver

Preferential vessels

Barriers: Blood-brain barrier (BBB)

Elastic arteries Muscular arteries Arterioles Capillaries Venules Medium-sized veins Large veins in the adventitia: vasa vasorum! Capacitance vessels

+Vasa vasorum, nerves (max. 5 +Vasa vasorum, nerves

Postcapillary venules

Venulen

Medium sized vessels Medium-sized vein Medium-sized artery Muscular vein

Valves in the veins Endothel-duplications Valve Skeletal muscle pump • Thrombosis, embolism, infarction • Thrombophlebitis • Cardiac bypass graft operation

Large vein

Special blood vessels glomerulus – portal veins

Receptors: carotid body (glomus) and sinus

1) Blood vessels 2) Lymph vessels