Mental health 3 Flashcards
What are the primary receptors for: opiates nicotine cannabis alcohol
opiates- mu receptors
nicotine- acetylcholine
cannabis- cannabinoid
alcohol- several, including gamma and NDMA receptors
What do most drugs of abuse secondarily act through?
Dopamine and mesolimbic reward system
What are 3 contributing factors to drug addiction?
Genetics- sensitivity and tolerance
social envrionment
personality and personal history
3 positives of using Drosophila to study drug addiction
quick and cost efficient to study their genetics
50% of drosophila genes are conserved in humans
75% of human genes implicated in disease are present in drosophila
What receptors do drosophila not have?
no mu or cannabinoid receptors
What are the two ways of measuring flies responses to ethanol?
The boozomat (paired with the locomoter velocity profile) The inebriometer
What is the ‘elution time’
The mean time at which the flies drop down the chamber (inebriometer)
What is the definition of sensitivity?
The inability to tolerate the adverse effects of a drug
How do we measure sensitivity?
Irradiate flies to induce random mutations
use the inebriometer
screen flies- use the flies that were the first and last to elute
identify the gene that was mutated
Which mutated gene is associated with increased sensitivity? What does the gene code for
Cheapdate
Its an allele for amnesiac , it encodes for a neuropeptide that activates the camp pathway
What is the definition of tolerance?
reducton in sensitivity when a drug is repeatedly used
How do we measure tolerance?
Repeate the inebriometer experiment multiple times
measure the elutiom time for mutant flies- see if it changes
screen the mutants- identify a gene
Which gene is associated with tolerance? What does it code for?
Hangover gene - defines a stress pathway requried for normal development of ethanol tolerance
Encodes a RNA binding protein
What is required for tolerance?
Turning off the camp pathway
What is dunce?
A camp phosphodiesterase
How does hangover and dunce interact?
They counteract each other
Hangover RNA binding protein binds dunce protein
The balance between hangover and dunce expression determines the degree of tolerance
What does DCO code for?
PKA subunit
What does dunce code for?
cAMP phosphodiesterase
What does rutabaga code for?
adenylate cyclase
What does cheapdate do?
Loss of the neuropeptide-
decreased activity of the cAMP pathway
What happens if you mutate both rutabaga and DCO?
ethanol-sensitive phenotype
DCO- reduction in cAMP stimulated PKA activity
