Opioids Flashcards
What class of opioids is defined by 3 fused benzene rings?
Phenanthrenes
____ is a phenanthrene derivative with two additional ring closures to the 3 benzene rings?
Morphine
____ is structurally the same as morphine, except with an ether substituted for an alcohol.
Codeine
Meperidine falls into the ____ class and was the first ___ opioid.
Phenylpiperidine
Synthetic
____ is the prototype phenylpiperidine. ___ and its congeners are also phenylpiperidines.
Meperidine
Fentanyl
Modification of morphine’s five ring structure resulted in the creation of ____ drugs.
Semisynthetic
Buprenorphine (partial agonist)
Naloxone and naltrexone (antagonists)
Natural agonists:
Morphine and codeine
Semisynthetic agonists:
Heroin and hydromorphone
Synthetic agonists:
Methadone, Fentanyl, Remifentanil, Meperidine, Sufentanil, Tramadol
____ is a semisynthetic partial agonist.
Buprenorphine
____ is a synthetic agonist-antagonist.
Nalbuphine
___ and ___ are semisynthetic antagonists:
Naloxone and Naltrexone
Mu, kappa, and delta opioid receptors are all what type of receptors?
GPCR
What is the “opioid motif”
Tyr - Gly - Gly - Phe - Leu/Met
*found on endogenous agonists
3 effects possible from binding at opioid receptor:
Inhibit adenylyl cyclase –> low cAMP –> decreased conductance of AP
Inhibit influx of Ca by messing up Ca channels
Increase potassium efflux preventing AP
Abrupt w/d of opioid = rebound disinhibition of cAMP causing hyperexcitability symptoms
Opioid Receptors found where in the brain? (5)
Periaqueductal Gray
Area Postrema
Limbic system
Cerebral cortex
Thalamus
brainstem modulates nociceptive transmission via inhibitory pathways of spinal cord
Opioid Receptors found where in spine?
Substantia geletinosa of dorsal horn
Inhibition of substance P release (pre-synaptically), and also blocking the transfer of pain up the cord
Big effects of mu receptor:
What endogenous ligand?
Bradycardia, respiratory depression, euphoria, sedation, miosis, N/v, urinary retention, pruritis, dependence
B-endorphin, endomorphin
Big effects of kappa receptor:
What endogenous ligand?
Less respiratory depression, dysphoria, miosis, diuresis, antishivering, low abuse profile
Dynorphin
T/F: For your next cardiac case you should use only opioids for anesthesia.
Wrongo. Not sufficient as an anesthetic by itself