Rat Kappa-type opioid receptor,Oprk1 ELI

G-protein coupled opioid receptor that functions as receptor for endogenous alpha-neoendorphins and dynorphins, but has low affinity for beta-endorphins.

Also functions as receptor for various synthetic opioids and for the psychoactive diterpene salvinorin A.

Ligand binding causes a conformation change that triggers signaling via guanine nucleotide-binding proteins (G proteins) and modulates the activity of down-stream effectors, such as adenylate cyclase.

Signaling leads to the inhibition of adenylate cyclase activity.

Inhibits neurotransmitter release by reducing calcium ion currents and increasing potassium ion conductance.

Plays a role in the perception of pain.

Plays a role in mediating reduced physical activity upon treatment with synthetic opioids.

Plays a role in the regulation of salivation in response to synthetic opioids.

May play a role in arousal and regulation of autonomic and neuroendocrine functions.

{ECO:0000269|PubMed:20358363, ECO:0000269|PubMed:8240267}.