“The endocannabinoid system plays a regulatory role in a number of physiological functions, including motor control but also mood, emotion, and cognition.
A number of preclinical studies in Parkinson’s disease (PD) models demonstrated that modulating the type 1 cannabinoid receptor (CB1R) may improve motor symptoms and components of cognitive processing. However, the relation between CB1R, cognitive decline and behavioral symptoms has not been investigated in PD patients so far.
The aim of this study was to examine whether CB1R availability is associated with measures of cognitive and behavioral function in PD patients.
CONCLUSIONS:
Decreased CB1R availability in the prefrontal and midcingulate cortex in PD patients is strongly correlated with disturbances in executive functioning, episodic memory, and visuospatial functioning. Further investigation of regional CB1R expression in groups of PD patients with mild cognitive impairment or dementia is warranted in order to further investigate the role of CB1R expression in different levels of cognitive impairment in PD.”
https://www.ncbi.nlm.nih.gov/pubmed/31342135
https://link.springer.com/article/10.1007%2Fs00259-019-04445-x
“Recent evidence has raised in discussion the possibility that
“We have previously reported that endocannabinoids modulate permeability in Caco-2 cells under inflammatory conditions and hypothesised in the present study that endocannabinoids could also modulate permeability in ischemia/reperfusion.
“The 
“The cannabinoid receptor CB1 is involved in modulation of neuronal hypersensitivity and pain. The aim of this study was to evaluate CB1 receptor levels for the first time in dental pain. A total of 19 patients due for molar extraction were divided into two groups, those with existing dental pain (n=9), and those with no history of pain (n=10). Immunohistochemistry and computer image analysis was used to evaluate CB1-positive nerve fibres in tooth pulp, with neurofilament-immunostaining as a structural nerve marker. CB1-immunoreactive nerve fibres were scattered throughout the tooth pulp and often seen in nerve bundles, but the fibres did not penetrate the subodontoblastic layer. There was no statistically significant change in the CB1 nerve fibre percentage area in the painful group compared to the non-painful group (p=0.146); the neurofilament fibres were significantly reduced in the painful group compared to the controls (p=0.028), but there was no difference in the ratio of CB1 to neurofilaments between the two groups. Thus, CB1 expression is maintained by nerve fibres in painful human dental pulp, and peripherally-restricted CB1 agonists currently in development may advance the treatment of dental pain.”
“The anti-depressant effect of repetitive transcranial magnetic stimulation (rTMS), a clinically-useful treatment for depression, is associated with changes to the endocannabinoid system (ECS).
“Much of the opioid epidemic arose from abuse of prescription opioid drugs.