Endocannabinoids work as retrograde messengers and contribute to short-term and long-term modulation of synaptic transmission via presynaptic cannabinoid receptors. It is generally accepted that the CB1 cannabinoid receptor (CB1) mediates the effects of endocannabinoid in inhibitory synapses. For excitatory synapses, however, contributions of CB1, "CB3," and some other unidentified receptors ha...

Mice devoid of CB1 cannabinoid receptors (CB1-/mice) provide a unique opportunity to further investigate the role of CB1 receptors in exocannabinoid and endocannabinoid effects. CB1-/mice (N=18) and their wild type littermates (CB1+/+ mice; N=12) were placed in standard mouse operant chambers and trained to lever press under a fixed-ratio 10 schedule of reinforcement. When stable lever press re...

The mammalian visual system exhibits significant experience-induced plasticity in the early postnatal period. While physiological studies have revealed the contribution of the CB1 cannabinoid receptor (CB1) to developmental plasticity in the primary visual cortex (V1), it remains unknown whether the expression and localization of CB1 is regulated during development or by visual experience. To e...

Presynaptic cannabinoid-1 receptors (CB1-R) bind endogenous and exogenous cannabinoids to modulate neurotransmitter release. CB1-Rs are expressed throughout the basal ganglia, including striatum and substantia nigra, where they play a role in learning and control of motivated actions. However, the pattern of CB1-R expression across different striatal compartments, microcircuits and efferent tar...

Effects of cannabinoids (CBs) are mediated by two types of receptors, CB1 and CB2. In this report, we investigated whether CBs regulate gene expression of their cognate receptors in T cells and studied underlying mechanisms in CD4+ Jurkat T cells. Transcription of the CB1 gene was strongly induced in response to Delta9-tetrahydrocannabinol (THC), whereas the CB2 gene was not regulated. The indu...

Previously, we found that in the lateral amygdala (LA) of the mouse, WIN55,212-2 decreases both glutamatergic and GABAergic synaptic transmission via activation of the cannabinoid receptor type 1 (CB1), yet produces an overall reduction of neuronal excitability. This suggests that the effects on excitatory transmission override those on inhibitory transmission. Here we show that CB1 activation ...

Corticostriatal circuits mediate various aspects of goal-directed behavior and are critically important for basal ganglia-related disorders. Activity in these circuits is regulated by the endocannabinoid system via stimulation of CB1 cannabinoid receptors. CB1 receptors are highly expressed in projection neurons and select interneurons of the striatum, but expression levels vary considerably be...

Psychoactive effects of cannabinoids are thought to be mediated, at least in part, by suppression of both glutamate and GABA release via CB1 cannabinoid receptor. Two types of cannabinoid receptor (CB1 and CB2) have been cloned so far. The CB1 receptors are abundantly expressed in the nervous system, whereas CB2 receptors are limited to lymphoid organs (Matsuda et al., 1990; Munro et al., 1993)...

The cannabinoid CB1 receptor system is critically involved in the control of associative fear memory formation within the amygdala-prefrontal cortical pathway. The CB1 receptor is found in high concentrations in brain structures that are critical for emotional processing, including the basolateral amygdala (BLA) and the prelimbic division (PLC) of the medial prefrontal cortex (mPFC). However, t...

Chronic voluntary wheel-running activity has been reported to hypersensitise central CB1 receptors in mice. On the other hand, pharmacological findings suggest that the CB1 receptor could be involved in wheel-running behaviour and in running-induced neurogenesis in the hippocampus. We analysed wheel-running behaviour for 6 weeks and measured its consequences on hippocampal neurogenesis in CB1 k...