OVERVIEW
This page is dedicated to compiling Step 1 study notes for the topic of opiate signaling. This page is likely disorganized as it was made in haste.
TYPES OF OPIATE RECEPTORS
There are 3 main time son opiate receptor subtypes:
- Mu
- Delta
- Kappa
OPIATE MU RECEPTORS
The opiate mu receptors are what exercise the strongest analgesic effects
Medications that bind these receptors:
Morphine/pain opiates: these have high affinity for the mu receptor
Mechanism of action/effect: This will depend on the site of the receptor.
- In the spine: opiates bind the receptor and this reslutls in the closure of voltage gated calcium channels (this causes reduced calcium influx). The ultimate result is decreased excitatory neurotransmitter release (such as acetylcholine etc) from the presynaptic terminal. This attenuates pain transmission (which produces analgesia).
- In the postsynaptic terminal: opiates also bind mu receptors that open potassium chillness and lead to membrane hperpolarizaiotn (due to potassium efflux).
Page Updated: 04.25.2017