Molecular Neuropharmacology Laboratory, School of Optometry and Ophthalmology and Eye Hospital, Wenzhou Medical University, Wenzhou, China.
Key Laboratory of Structural Malformations in Children of Zhejiang Province, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, China.
Neuropsychopharmacology. 2023 Sep;48(10):1520-1531. doi: 10.1038/s41386-023-01533-3. Epub 2023 Jan 24.
Several cognitive processes, including instrumental behavior and working memory, are controlled by endocannabinoids acting on cannabinoid receptor 1 (CB1R) in the brain through retrograde and presynaptic inhibition of GABA or glutamate release. However, the temporal mechanisms underlying the control of these cognitive processes by CB1Rs remain largely unknown. Here, we have developed a light-sensitive CB1R chimera (optoCB1R) by replacing the intracellular domains of bovine rhodopsin with those of human CB1R. We demonstrated that light stimulation of optoCB1R triggered canonical CB1R signaling by inhibiting cAMP (but not cGMP or IP1) signaling and activating the MAPK pathway in vitro or in vivo. Moreover, light stimulation of optoCB1R in corticostriatal glutamatergic neurons could temporally inhibit excitatory postsynaptic currents (EPSCs) at the level of seconds. Importantly, transient (3 s) and "time-locked", but not random, activation of optoCB1R signaling in corticostriatal neurons at the time of reward affected animal sensitivity to outcome devaluation and inhibited goal-directed behavior. However, prolonged (~30 min) but not transient (10 or 30 s) activation of astrocytic CB1R signaling in the hippocampus impaired working memory. Consequently, neuronal and astrocytic CB1R signaling differentially regulate working memory and goal-directed behavior through distinct temporal and cellular mechanisms. Ultimately, the pharmacological blockade of adenosine AR improved the neuronal and astrocytic CB1R-induced impairments in goal-directed behavior and working memory, possibly through modulation of EPSCs and c-Fos, respectively. Therefore, AR may represent a promising target for managing cognitive dysfunction resulting from the use of CB1R drugs.
几种认知过程,包括工具性行为和工作记忆,受内源性大麻素的控制,内源性大麻素通过逆行和突触前抑制 GABA 或谷氨酸释放作用于大脑中的大麻素受体 1(CB1R)。然而,CB1R 控制这些认知过程的时间机制在很大程度上仍然未知。在这里,我们通过用人类 CB1R 的细胞内结构域替换牛视紫红质的细胞内结构域,开发了一种光敏感的 CB1R 嵌合体(optoCB1R)。我们证明,光刺激 optoCB1R 通过抑制 cAMP(但不抑制 cGMP 或 IP1)信号和激活 MAPK 途径在体外或体内触发典型的 CB1R 信号。此外,光刺激 optoCB1R 在皮质纹状体谷氨酸能神经元中可以在数秒的时间内暂时抑制兴奋性突触后电流(EPSC)。重要的是,在奖励时,皮质纹状体神经元中 optoCB1R 信号的短暂(3s)和“时间锁定”(而非随机)激活会影响动物对结果贬值的敏感性并抑制目标导向行为。然而,海马体中星形胶质细胞 CB1R 信号的延长(~30min)而不是短暂(10 或 30s)激活会损害工作记忆。因此,神经元和星形胶质细胞 CB1R 信号通过不同的时间和细胞机制差异调节工作记忆和目标导向行为。最终,腺苷 A2A 受体的药理学阻断改善了神经元和星形胶质细胞 CB1R 诱导的目标导向行为和工作记忆障碍,可能分别通过调制 EPSC 和 c-Fos。因此,A2A 受体可能代表一种有希望的治疗因使用 CB1R 药物引起的认知功能障碍的靶点。