Arteries
Blood Vessels
Aorta, Arteries and Arterioles
Fundamentals:
- Aorta is the largest artery
- Strong and thick walls
Function:
- Carry blood AWAY from the heart
- Major area of resistance - Arterioles and have strong muscular walls
- Meaning that the largest drop in BP occurs at the arterioles
- WHY? Arteriole's hydrostatic pressure is relatively high
Anatomy:
- Lumen
- Lined with endothelial cells
- Tunica intima
- Tunica media
- Tunica externa
- Smooth muscle
- Connective tissue
- Collagenous fibers
- Elastic fibers
Specifications/Fundamentals:
- Total cross sectional area 5cm^2
- Blood pressure 80-120 mmHg (average 100 mmHg)
- Volume of blood 16-20%
- Velocity 30 cm/s
Concept:
- Blood Pressure Measurement
- pressure that the baroreceptors are sensing as they monitor blood pressure"
- Stethoscope on antecubital artery
- Cuff inflated above arterial systolic pressure
- Pressure of the cuff is decreased (manipulated using the turn nob at the pump)
- The pressure below the systolic blood will jet through the artery
- Turbulent flow because great pressure pushes through narrow area
- Sound marks systolic
- Pressure of the cuff is further decreased and the vessel regains original shape.
- Turbulent flow becomes laminar flow
- Change in sound marks diastolic pressure
- Regulation
- Autonomic Nervous System
- Sympathetic - important in ANS
- Parasympathetic
- Hormonal regulation
- Local tissue regulation
- Metabolites circulate in the tissue and diffuse out to the blood vessels
- Smooth muscle dialates to increase flow to particular area
Disorders/Diseases:
- Atherosclerosis
- Abrasion through pressure or substances allow choleserol/plaque to build up
Terminology:
- Diastolic pressure - Heart
- Systolic pressure - Heart
- Blood Pressure: force/area of the body fluid exclusively in vessels
- Baroreceptors - Heart
- Endothelial cells: inside the cardiovascular system
