lecture 13 LOs Flashcards
what do opiod narcotic analgesics do
reduce pain without producing unconsciousness
what is the main ingredient in opium
morphine
what is heroin made of (chemical structure)
morphine with 2 acetyl groups added to it (making it more lipid soluble)
where are opioid receptors found in the body
in the brain (receptors found w radioligand binding) and also in the gut
what are endogenous opioid receptor subtypes
mu, delta, kappa, and the nociceptin/orphanin FQ receptor (aka NOP-R)
what type of receptors are found in the endogenous opioid system
g protein linked metabotropic receptors
mu receptor has high affinity for what
morphine
what does the regional distribution of mu mean regarding its effects
periaqueductal grey: analgesia
brain stem: cardiovascular/respiratory control, cough control, vomiting
thalamus: sensorimotor integration
NAc: feeding, positive reinforcement
where is the delta endogenous opioid found
predominantly in the forebrain structures
suggests roles in olfaction, motor integration, reinforcement, cognitive function
reduced activity causes anxiety
kappa receptors have distribution to where
striatum, amygdala, hypothalamus
may play a role in pain perception, fut motility, dysphoria
what does NOP do
does not bind to opioid drugs
role in analgesia, feeding, learning, motor function, reward and neuroendocrine regulation
NOP agonists have minimal abuse potential and cause less respiratory depression
what are endorphins
peptides that activate opioid receptors
what are endogenous opioid peptides synthesized from
larger precursor peptides then cleaved to smaller peptide transmitters
what type of amino acid sequences do propeptides have
for both endogenous opiates and other transmitters
what are two ways that opioid transmitters can be released
via long axonal projection systems, or by local circuit neurons
are endogenous opioids selective
no, they show a relative preference
what are mu receptors preferentially activated by
endorphins and somewhat by endomorphins
what are delta receptors preferentially activated by
enkephalins and endorphins