There is a lot of information available about both the role of cannabinoid receptors in human brain and their involvement in brain disorders.
As an example our papers about these receptors characterization in normal human brain and postmortem brain of schizophrenic subjects:
-López de Jesús M.; Sallés J.; Meana J.J.; Callado L.F. “Characterization of CB1 cannabinoid receptor immunoreactivity in postmortem human brain homogenates” Neuroscience 140:635-643 (2006).
-Urigüen L.; García-Fuster M.J.; Callado L.F.; Morentin B.; La Harpe R.; Casadó V.; Lluis C.; Franco R.; García-Sevilla J.A. ; Meana J.J. “Immunodensity and mRNA expression of A2A adenosine, D2 dopamine and CB1 cannabinoid receptors in postmortem frontal cortex of schizophrenic subjects: Effect of antipsychotic treatment”. Psychopharmacology 206:313-324 (2009).
dear paul,
as luis mentionned, you can find a good amount of reviews on the role of cannabinoid receptor in brain functions as well as the role/modulation of endocannabinoids...
"cannabinoid brain human review" gets 700+ hits in pubmed.. I am sure you'll find your answers in there!
best
agreed with the above. It largely serves a regulatory purpose in the brain, ie by retrogradely regulating neurotransmitter release at the pre-synaptic level. I am simplyfying a great deal of course, but its a good "fact of thumb" to hang your hat on.
Just to add: the orthodox view is that the CB1 receptor is the relevant one in the CNS. However, inflammatory cytokines activate and regulate the activity of glial and neurons, and may themselves be released from glial cells. Monocytes in the CNS harbor CB2 receptors, hence, the effect of CB2 receptors shoudl not be readily dismissed from the real of CNS influences
The cannabinoid receptors are a class of cell membrane receptors under the G protein-coupled receptor superfamily. As is typical of G protein-coupled receptors, the cannabinoid receptors contain seven transmembrane spanning domains. Cannabinoid receptors are activated by three major groups of ligands, endocannabinoids (produced by the mammalian body), plant cannabinoids (such as THC, CBD etc. produced by the cannabis plant) and synthetic cannabinoids (such as HU-210). All of the endocannabinoids and plant cannabinoids are lipophilic, i.e. fat soluble, compounds.
Cannabinoid receptor type 1 (CB1) receptors are thought to be one of the most widely expressed G protein-coupled receptors in the brain. This is due to endocannabinoid-mediated depolarization-induced suppression of inhibition (retrograde signaling), a very common form of short-term plasticity in which the depolarization of a single neuron induces a reduction in GABA-mediated neurotransmission. Endocannabinoids released from the depolarized post-synaptic neuron bind to CB1 receptors in the pre-synaptic neuron and cause a reduction in GABA release.