Lipid Mediators (Endocannabinoids):

Derived from the conversion of eicosanoids to endocannabinoids

Act on CB1 receptors to inhibit GABA and glutamate release

Functions: Involved in vomiting (CB1 agonists block it), multiple sclerosis (MS), pain, anxiety, and weight loss (e.g., rimonabant as a CB1 antagonist)

Melatonin:

Acts on MT1 and MT2 receptors

Functions: Involved in sleep regulation, circadian rhythmicity, and used as an agonist for jet lag and insomnia

Review: Neurotransmitters Systems III: Monoamines (Physiology 2)