In the olfactory system, the endocannabinoid system (ECS) regulates sensory perception and memory. A major structure involved in these processes is the anterior piriform cortex (aPC), but the impact of ECS signaling in aPC circuitry is still scantly characterized. Using ex vivo patch clamp experiments in mice and neuroanatomical approaches, we show that the two major forms of ECS-dependent synaptic plasticity, namely depolarization-dependent suppression of inhibition (DSI) and long-term depression of inhibitory transmission (iLTD) are present in the aPC. Interestingly, iLTD expression depends on layer localization of the inhibitory neurons associated with the expression of the neuropeptide cholecystokinin. Conversely, the decrease of inhibitory transmission induced by exogenous cannabinoid agonists or DSI do not seem to be impacted by these factors. Altogether, these results indicate that CB1 receptors exert an anatomically specific and differential control of inhibitory plasticity in the aPC, likely involved in spatiotemporal regulation of olfactory processes.

在嗅觉系统中，内源性大麻素系统（ECS）调节感觉知觉和记忆。这些过程中涉及的主要结构是梨状前皮质（aPC），但是ECS信号在aPC电路中的影响仍然很少。离体使用在小鼠和神经解剖学方法的膜片钳实验中，我们显示出aPC中存在两种主要形式的ECS依赖突触可塑性，即去极化依赖的抑制抑制（DSI）和长期抑制性抑制传递（iLTD）。有趣的是，iLTD表达取决于与神经肽胆囊收缩素表达相关的抑制性神经元的层定位。相反，外源性大麻素激动剂或DSI诱导的抑制性传递的降低似乎不受这些因素的影响。总而言之，这些结果表明CB1受体在aPC中发挥解剖学特异性和差异性控制其抑制性可塑性，可能参与嗅觉过程的时空调节。