Physiology
Neuronal Control Of Blood Vessels
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Get accessMediated by the sympathetic system except from in sweat and salivary glands (parasympathetic)
- Alpha1 receptors: vasoconstriction
Inositol triphosphate (IP3) is a second messenger increased by alpha adrenoceptors. Binds to the ER and increases calcium concentrations leading to smooth muscle contraction, increased cardiac rate and force of contraction and exocrine secretions
- Beta2 receptors: vasodilation (NB: adrenaline mediates this)
- Noradrenaline: vasoconstriction via alpha receptors
- Angiotensin II: vasoconstriction
- Histamine and bradykinin: vasodilation