Enhanced long-term potentiation in mice lacking cannabinoid CB1 receptors

Neuroscience. 2000;95(1):5-7. doi: 10.1016/s0306-4522(99)00483-2.


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.

MeSH terms

  • Animals
  • Electric Stimulation / methods
  • Excitatory Postsynaptic Potentials / physiology
  • Female
  • Hippocampus / physiology
  • In Vitro Techniques
  • Long-Term Potentiation / physiology*
  • Male
  • Mice
  • Mice, Knockout / genetics
  • Neuronal Plasticity / physiology
  • Receptors, Cannabinoid
  • Receptors, Drug / deficiency*
  • Receptors, Drug / genetics
  • Reference Values
  • Synapses / physiology


  • Receptors, Cannabinoid
  • Receptors, Drug