๐ > Pharmacology > Autonomic Nervous System > Adrenergic_>
Adrenergic Transmission
Adrenergic Transmission
Neurotransmitter: Noradrenaline (Norepinephrine)
Sites
Sympathetic postganglionic neuron.
Except: Sweat glands, some vasodilator fibers
Brain
Steps
Tyrosine
โ Tyrosine hydroxylase
DOPA
โDOPA decarboxylase
Dopamine
โ
Transported into the vesicle by Vesicular Monoamine Transporter (VMAT)
โ
Dopamine
โฮฒ hydroxylase
Noradrenaline
โ
Complexed with ATP โถ adsorbed on chromogranin
โ
Nerve impulse coupled release
โ
Acts on adrenergic receptors on postsynaptic membrane
โ
1. 75-90% is taken back in nerve terminal by Norepinephrine transporter(NET) โถ most of it is transported into the vesicle by VMAT; some is degraded by Monoamine Oxidase (MAO).
2. Some noradrenaline diffuses away โถ Degraded by Catechol O Methytransfarase (COMT).