PSYC62H3 Chapter Notes - Chapter 10: Thalamus, Metabotropic Receptor, Enkephalin
Document Summary
Opioids- psychoactive drug w/ pharmacological effects (pain-relieving, sleep-inducing); Abusive- reinforcing effects and easy access (over-the-counter, prescription) Naturally occurring- found in opium: morphine (ii)& codeine (iii/iv)) Synthetically produced- from morphine and codeine; heroin, oxycodone(oxy contin), tylenol (oxycodone and acetaminophen) Oral administration, inhalation, intravenous injection rapid onset; mainly preferred for recreational use; intravenous provides faster pain relief. Opioids permeate the bbb (lipid solubility varies with type); heroin enters more readily than morphine. Metabolized in the liver producing metabolites: morphine produces morphine-6-glucoronide- analgesic o codeine morphine - morphine-6-glucoronide heroin- monoacetylmorphine morphine - morphine-6-glucoronide acetylcodeine- codeine-morphine- morphine-6-glucoronide o o. Elimination: methadone stays active 24 hours after administration; used to combat heroin withdrawal symptoms. Endogenous neurotransmitters: neuropeptides produced from propeptides: o o o proopiomelanocortin: produces -endorphin proenkephalin: met-enkephalin, leuenkephalin prodynorphin: dynorphin a, dynorphin b, neoendorphin. ***strand of amino acid is a peptide; long peptide= propeptide; shorter/segment= cleavage .
