Synthetic k2 spice are a class of molecules that bind to the same receptors to which cannabinoids (THC and CBD) in cannabis plants attach. Most synthetic herbal incense are agonists of the cannabinoid receptors.
Many of these compounds act as synthetic cannabinoids 1, 2, or 3. CB1 receptors are the most abundant receptors in brain. They are mainly found in the forebrain and limbic structures. The CB1 receptors are stimulated by endocannabinoids, an internal messenger that plays an important role in homeostasis. Endocannabinoids also bind to GPR55, a peripheral receptor for GABA.
CB1 receptors are implicated in memory and learning. CB1 receptors are stimulated by neuropeptides, natural pain killers, neurotrophic factors that promote cell survival, endocannabinoid ligands, and serotonin. The effect of CB1 receptor stimulation is to increase monoamine levels, attention, motor coordination, memory, and sleep. CB1 receptor stimulation also may lead to dysfunction in dopamine, serotonin, and noradrenalin systems, which may contribute to the neurocognitive effects. This explains why k2 have been shown to cause psychosis in mice.
People with anxiety experience disorientation, sudden aggression and hallucinations when using synthetic cannabinoids. The effects of k2 are generally felt less intensely than THC, so many users enjoy consuming them. Another effect of high-frequency stimulation of CB1 receptors is the elevation in cytokines that promote inflammation and regeneration. The cytokines stimulate the growth of microglia, another type of immune cell present in the brain. The microglia are associated with the generation of neuroinflammatory cytokines and neurotoxins that can worsen psychiatric disorders. Research has found that high-frequency stimulation of CB1 receptors leads to higher severity of symptoms in treatments for depression. CB2 receptors are also found on the CB1 receptors in the brain. They differ from CB1 receptors in their expression, efficiency of binding at the receptors, and lack the psychedelic or euphoric effects of synthetic cannabinoids.
CB2 receptors are more common in the periphery than CB1 receptors and also affect motor coordination, cognition, sleep, and learning. They are mainly found at higher concentrations in the periphery and peripheral nerve endings. CB2 receptors bind to gamma-aminobutyrate (GABA) receptors, another neurotransmitter that can regulate memory and learning and activity. Consistent with this, some clinical trials have found that CB2 receptor stimulation is effective in treating memory disorders. CBNs can mimic more than one cannabinoid receptor subtype. The main difference is that new psychoactive compounds cannot be isolated from the plant or treated as individual molecules.
A synthetic cannabinoid is basically an artificial representation of the cannabinoids derived from plants and grows in the human body similar to naturally occurring cannabinoids in the bloodstream. Synthetic cannabinoids are ‘highly complex’, making identification of the active ingredient challenging. The binding affinities of CB1 and CB2 receptors to individual cannabinoids can differ by up to threefold.