primary amine neurotransmitter Flashcards
principles of neurotransmitter action?
synthesis, storage, release, receptors, removal, degradation, drugs and disease
dopamine is the precursor for?
noradrenaline
brain dopamine pathways?
nigrostriatal pathway, mesolimbic pathway, mesocortical pathway, and tuberoinfundibular pathway.
what does the nirostriatal pathway control?
movement
what does the mesolimbic pathway control?
increases responsiveness to external and internal stimuli
what does the mesocortical pathway control?
normal cognition, motivation and emotions
what does the tuberoinfundibular pathway control?
arcuate nucleus (hypothalamus) to median eminence, prolactin release from anterior pituitary
what metabolises dopamine?
MAO and COMT
how does cocaine affect dopamine transmission?
inhibits DAT so acts as a stimulant, addictive
how does amphetamine affect dopamine transmission?
increases DA release, inhibits uptake, acts as a stimulant and induces psychosis. addictive
how does L-DOPA affect dopamine transmission?
precursor for dopamine, increases DA formation. treats parkinson’s
how do MAOb and COMT inhibitors affect dopamine transmission?
reduce DA metabolism and L-DOPA metabolism. treats parkinson’s
how do dopamine agonists affect dopamine transmission?
activate DA receptors to treat parkinson’s
what are the two noradrenlaine pathways/nuclei?
locus coreuleus and caudal raphe nuclei
what metabolises noradrenaline?
COMT and MAOa
adrenergic receptors of noradrenaline?
alpha1, alpha2, beta1, beta2
how do alpha2 noradrenaline receptors act presynaptically?
inhibit transmitter release, inhibit voltage dependent ca channels
how do alpha1 noradrenaline receptors act postsynaptically?
activate PLC, increase IP3 and DAG, increase calcium
how do alpha2 noradrenaline receptors act postsynaptically?
inhibit adenylate cyclase
activate K+ channels
increase k+ efflux
inhibit voltage dependent calcium channels
how does amphetamine affect noradrenaline transmission?
displaces NA from vesicles, MAO inhibitor, increases NA release. acts as stimulant, induces psychosis, addictive
how does cocaine affect noradrenaline transmission?
inhibits NET, acts as stimulant, addictive
how do antidepressants affect noradrenaline transmission?
inhibit NET so useful in depression
how does ephedrine affect noradrenaline transmission?
increases NA release, B agonist, CNS stimulant, used as nasal decongestant
how do monoamine oxidase inhibitors affect noradrenaline transmission?
inhibits MAO so reduces NA metabolism, treats depression
