Endocannabinoids facilitate the induction of LTP in the hippocampus.
Exogenous cannabinoids disrupt behavioral learning and impede induction of long-term potentiation (LTP) in the hippocampus, yet endogenous cannabinoids (endocannabinoids) transiently suppress inhibitory post-synaptic currents (IPSCs) by activating cannabinoid CB1 receptors on GABAergic interneurons. We found that release of endocannabinoids by a rat CA1 pyramidal cell during this depolarization-induced suppression of inhibition (DSI) enabled a normally ineffective train of excitatory post-synaptic currents (EPSCs) to induce LTP in that cell, but not in neighboring cells. By showing that endocannabinoids facilitate LTP induction and help target LTP to single cells, these data shed new light on the physiological roles of endocannabinoids and may lead to a greater understanding of their effects on behavior and potential clinical use.
Carlson
Gregory
G
Department of Physiology, University of Maryland School of Medicine, 655 West Baltimore Street, Baltimore, Maryland 21201, USA.
Wang
Yue
Y
Alger
Bradley E
BE
D000818:Animals; D063385:Cannabinoid Receptor Modulators; D002186:Cannabinoids / Q000494:pharmacology*; D004558:Electric Stimulation / Q000379:methods; D063388:Endocannabinoids; D019706:Excitatory Postsynaptic Potentials / Q000187:drug effects / Q000502:physiology; D018756:GABA Antagonists / Q000494:pharmacology; D058787:GABA-A Receptor Antagonists; D006624:Hippocampus / Q000187:drug effects* / Q000502:physiology*; D066298:In Vitro Techniques; D017774:Long-Term Potentiation / Q000187:drug effects* / Q000502:physiology*; D018408:Patch-Clamp Techniques; D017966:Pyramidal Cells / Q000187:drug effects / Q000502:physiology; D051381:Rats
D063385:Cannabinoid Receptor Modulators; D002186:Cannabinoids; D063388:Endocannabinoids; D018756:GABA Antagonists; D058787:GABA-A Receptor Antagonists