Physiology of arteries
Mean arterial blood pressure in the arteries which is about 100 mm Hg is smaller than that of the aorta but higher than other vessels in the body from arteriole to capillary to veins and venules. The total cross sectional area is a little higher than that of aorta but much more smaller than the capillary which has about 4500 cm2 as opposed to 4.5 cm2 in aorta. The relative resistance is lower than arteriole and veins while the velocity of blood flow is almost as high as in aorta which is much higher than the rest of the vessels of the body.
The myocytes in the tunica media are under the control of autonomic nervous system which help to determine their luminal size and their contraction. Sympathetic system cause vasoconstriction while parasympathetic cause vasodilatation.
Peripheral vascular resistance helps to determine arterial pressure. The
smaller the diameter of the lumen, the higher is the peripheral resistance
and hence the higher the pressure.
Blood vessels physiology