Class Notes (834,807)
Canada (508,727)
Psychology (2,710)
PSYC 3403 (166)
Lecture 9

Lecture 9.docx

9 Pages
Unlock Document

PSYC 3403
Tarry Ahuja

Lecture 9 Overview - Pain (acute vs. chronic) - Opioids - Opioid receptors - Morphine Pain - Two classifications • Acute pain • Chronic pain - Acute pain: • Caused by soft tissue damage • Infection • Inflammation • Short term - Chronic pain: • Linked with long-term illness or disease • May have no apparent cause (no obvious wound) • Can trigger other issues • Difficult to assess and diagnose • Long term Pain - Nociception • Refers to the system that carries signals of damage and pain to the brain • Nociceptive neurons have cell bodies in the dorsal root ganglia • Can detect mechanical, thermal (ex: hot water), and chemical (ex: acid) stimuli - Nociception transmission: • Bidirectional axons synapse in dorsal horn of the spinal cord • Signal continues to brain where its processed (signal crosses horn and up to brain) Opioids - Can modulate symptoms of pain - Mimics endogenous endorphins/enkephalins - Bind to opioid receptors - Opioid agonists Opioids (sources) **KNOW THIS!!** - Natural: • From the resin of poppy seeds • Morphine, codeine, thebaine - Semi-synthetic: • Created from natural opioids (but have been modified) • Heroin, oxycodone, hydromorphone - Fully synthetic: • Derived in a lab • Methadone, fentanyl Opioids - Derived from the resin of the opium poppy (Papaver somniferum, “sleep-bringing poppy”) - Harvested primarily for medicinal purposes - There is a world-wide shortage - US buys 80% of its supply from India and Turkey Opioid receptors - Three types of receptors: • Mu ( µ ;µ 1,µ 2,µ 3) • Kappa (K; K , 1 , 2 ) 3 • Delta (;1, 2, 3 ) - Up to 17 types have been reported - Differential distribution in the brain Opioid receptors - Mu receptors are found in: • Thalamus • Striatum • Spinal cord • Periaquaductal gray • Brainstem nuclei - Has analgesic effects, alters respiration Opioid receptors - Kappa receptors are found in: • Basal ganglia • Nucleus accumbens • Hypothalamus • Periaquaductal gray • Deep cerebral cortex - May antagonize mu receptor activity - Modest analgesia, Dysphoria, little or no respiratory depression Opioid receptors - Delta receptors are found in: • Nucleus accumbens • Limbic system • Spinal cord - Lower addictive potential - Modulate the activity of mu receptors - Poor analgesics Opioid receptors (classification) - Pure agonists: • Strong binding to receptor • Ex: morphine (mu receptor) - Pure antagonists: • Strong binding to receptor with no activity • Ex: naltrexone (mu
More Less

Related notes for PSYC 3403

Log In


Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.