Abstract
Our sensory systems such as the olfactory and visual systems are the target of neuromodulatory regulation. This neuromodulation starts at the level of sensory receptors and extends into cortical processing. A relatively new group of neuromodulators includes cannabinoids. These form a group of chemical substances that are found in the cannabis plant. Δ9-tetrahydrocannabinol (THC) and cannabidiol (CBD) are the main cannabinoids. THC acts in the brain and nervous system like the chemical substances that our body produces, the endogenous cannabinoids or endocannabinoids, also nicknamed the brain’s own cannabis. While the function of the endocannabinoid system is understood fairly well in limbic structures such as the hippocampus and the amygdala, this signaling system is less well understood in the olfactory pathway and the visual system. Here, we describe and compare endocannabinoids as signaling molecules in the early processing centers of the olfactory and visual system, the olfactory bulb, and the retina, and the relevance of the endocannabinoid system for synaptic plasticity.
Highlights
Along their pathways, neural elements of sensory systems are targeted by a variety of modulatory regulators
THC acts in the brain and nervous system like the chemical substances that our body produces, the endogenous cannabinoids or endocannabinoids, nicknamed the brain’s own cannabis (Nicoll and Alger, 2004)
While the basic signaling functions of the endocannabinoid system are understood relatively well in limbic structures such as the hippocampus and the amygdala, this signaling system is less well understood in the olfactory pathway (Terral et al, 2020; Heinbockel et al, 2021) and visual system
Summary
Neural elements of sensory systems are targeted by a variety of modulatory regulators. The two main eCBs that have been primarily implicated in cannabinoid signaling are 2arachidonoyl glycerol (2-AG, Mechoulam et al, 1995; Sugiura et al, 1995) and arachidonoyl ethanolamine (AEA, anandamide, Devane et al, 1992) These lipid messengers are derived from membrane lipids upon neuronal activation and are broken down enzymatically, extracellularly after receptor activation. Many CB1 expressing neurons in the CNS are GABAergic (Tsou et al, 1998) In these cases, eCBs activate CB1 at presynaptic terminals to reduce transmitter release, either glutamate (Lévénés et al, 1998; Takahashi and Linden, 2000; Kreitzer and Regehr, 2001b) or GABA (Katona et al, 1999; Hoffman and Lupica, 2000; Ohno-Shosaku et al, 2001; Varma et al, 2001; Wilson and Nicoll, 2001; Diana et al, 2002). The review will conclude with a comparison of key findings for both sensory systems and an outlook for future research questions
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
