Enhanced long-term potentiation in mice lacking cannabinoid CB1 receptors.
Marijuana is known to affect learning and memory in humans, and cannabinoids block long-term potentiation in the hippocampus, a model for the synaptic changes that are believed to underlie memory at the cellular level. We have now examined the physiological properties of the Schaffer collateral-CA1 synapses in mutant mice in which the CB1 receptor gene has been invalidated and found that these animals exhibit a half-larger long-term potentiation than wild-type controls. Other properties of these synapses, such as paired-pulse facilitation, remained unchanged. This indicates that disrupting CB1 receptor-mediated neurotransmission at the genome level produces mutant mice with an enhanced capacity to strengthen synaptic connections in a brain region crucial for memory formation.
Bohme
G A
GA
Department of Neurophysiology, Rhône-Poulenc Rorer S.A., Centre de Recherches de Vitry-Alfortville, Vitry-Sur-Seine, France. bohme@rp.fr
Laville
M
M
Ledent
C
C
Parmentier
M
M
Imperato
A
A
D000818:Animals; D004558:Electric Stimulation / Q000379:methods; D019706:Excitatory Postsynaptic Potentials / Q000502:physiology; D005260:Female; D006624:Hippocampus / Q000502:physiology; D066298:In Vitro Techniques; D017774:Long-Term Potentiation / Q000502:physiology*; D008297:Male; D051379:Mice; D018345:Mice, Knockout / Q000235:genetics; D009473:Neuronal Plasticity / Q000502:physiology; D043882:Receptors, Cannabinoid; D011955:Receptors, Drug / Q000172:deficiency* / Q000235:genetics; D012016:Reference Values; D013569:Synapses / Q000502:physiology
D043882:Receptors, Cannabinoid; D011955:Receptors, Drug