Noradrenergic Signalling Flashcards
Other names for noradrenaline
norepinephrine
Automatic Signaling
Involuntary. Eg balance, breathing, heart pumping. 2 components: sympathetic and parasympathetic
Somatic signalling
Voluntary. Eg walking
Sympathetic Signaling Outline
Main neurotransmitter: noradrenaline. Signals mainly come from ganglia in spine. Positive chontropy (faster rate) and positive ionotropy (stronger magnitude of muscle contraction)
Sympathetic nerves
Shorter presynaptic nerve that releases Acetylcholine. Longer postsynaptic nerve releases noradrenaline. Acts on adregeneric receptors on effector muscles
Catecholamine Neurotransmitters Outline
Molecules with a benzene ring with 2 adjacent hydroxyl groups and an amine side chain (mollecules are differentiated by their amino side chains
Noradrenaline Synthesis
Precursor: L Tyrosine. Converted by tyrosine hydrolase to DOPA. Converted by DOPA decarboxylase to dopamine. Converted by dopamine beta-hydroxylase to noradrenaline. ATP dependent process
Noradrenaline Termination of Action
neuronal uptake and extra-neuronal uptake and
Neuronal Uptake Outline
Noradrenaline Transporters and vesicular monoamine transporter into vesicles
Noradrenaline Metabolism
monoamine oxidase works in presynaptic neuron to oxidise (prevent functioning of noradrenaline. catechol-O-methyl transferase adds a methyl group to noradrenaline in post synaptic tissues
Androgenic receptor types
G-protein couples receptors. Alpha 1, alpha 2, beta 1, beta 2 and beta 3
Alpha 1 Outline
Post synaptic. Increases Ca^2+, increased diglycerol and increased inositol triphosphate (phospholipase C production). Function: smooth muscle contraction, glycogenesis. Arteriole constriction, vein consitriction, viscous saliva secretion, bladder sphnicter constriction
Alpha 2 Outline
Presynaptic receptor. Decreases cAMP, decreases Ca channel firing. Function: noradrenaline inhibition
Beta 1 Outline
Post synaptic receptor. Increase cAMP production. Smooth muscle contraction
Sympathetic response
Increase heart rate and muscle contraction magnitude, dilation of pupils and heart rate, increase glucogenesis
Catecholamine Function on Heart rate
B1s increase heart rate and contraction magnitude (opposed by parasympathetic M2 receptor)
