Vascular System
Layers of Arteries
| Layer | Elastic Artery | Muscular Artery | Arteriole |
|---|---|---|---|
| Tunica adventitia | + | + | + |
| External elastic layer | - | Elastin | - |
| Tunica media | Elastin | Smooth muscle | Smooth muscle |
| Internal elastic layer | - | Elastin | - |
| Tunica intima | + | + | + |
LaPlace's Law
| Parameter | γ ∝ P × R ÷ T |
|---|---|
| γ | Surface tension |
| P | Pressure difference |
| R | Radius |
| T | Thickness |
Hormones Acting on Vessels
| Hormone | Receptor | Effect |
|---|---|---|
| Norepinephrine | α1 | Vasoconstriction |
| Epinephrine | β2 | Vasodilation |
| α1 | Vasoconstriction | |
| Dopamine | D1 | Vasodilation |
| α1 | Vasoconstriction | |
| Serotonin | 5-HT1 | Vasodilation Vasoconstriction |
| 5-HT2 | Vasoconstriction | |
| Histamine | H1 | Vasodilation |
| Angiotensin | AT1 | Vasoconstriction |
| Vasopressin | V1 | Vasoconstriction |
| Adenosine | A1 | Vasodilation |
| Prostaglandin | PGE1 | Vasodilation |
| Prostacyclin | PGI2 | Vasodilation |
| Thromboxane | TXA2 | Vasoconstriction |
| Endothelin | ETA | Vasoconstriction |
| Bradykinin | B1 | Vasodilation |
| Substance P | NK1 | Vasodilation |
| Nitric oxide | - | Vasodilation |