acetylcholine Flashcards
what are subtypes of nachrs
muscle type and neuronal
muscle type subunits: alpha 1, beta 1 gamma, delta, epsilon
neuronal alpha 2-10, beta 2-4
what do subunits determine
functional properties of receptor including desensitisation
what are the main nAchR subtypes in the CNS
alpha4beta2 either 2 or 3 of each alpha 7 (5 alpha 7 subunits)
alpha 7 activates and desensitises fast, has high calcium permeability
alpha4beta2 has slow activation and slow desensitisation with low calcium permeability
what might nachr knockouts do in transgenic mice
alpha 1: loss of nerve evoked muscle endplate potentials
alpha 4: loss of nicotine induced release of dopamine in brain
alpha 3: severe autonomic/ganglionic loss of function
what disease can certain types of nachr mutations cause
several nachr point mutations have been associated with autosomal dominant nocturnal frontal lobe epilepsy
what nachr is a target for schizo treatment
alpha 7, since it is located in brain areas associated with cognition
what main nachr subtypes affect parkinsons
a6beta2* a4b2* a7 since they are in the nigrostriatal pathway
amyloid beta also interacts with a7 and b2* which disrupts their role
what cholinergic neurones are lost in alzheimers
neurones in the basal forebrain
how does chronic exposure to nicotine affect the CNS
causes upregulation of brain nAchrs also causes desensitisation of a4b2 nachrs
which subunit types are implicated in mediating the addictive effects of nicotine
a4 and b2
what is a treatment for nicotine addiction
nicotine gum as well as varenicline which is a partial agonist of a4b2 nachrs
what type of receptors are machrs
GPCRs
where are the different machrs found
m1/3/5 are found mostly postsynaptically
2/4 act both pre and post synaptically
only m2/4 exhibit feedback control over ach release
