协同激活CB1和GPR55促进GABA释放和运动行为,通过增加由CB1激活诱导的二分化,在条性终端通过增加的二分化
José Arturo Avalos-Fuentes1, Rodolfo Sánchez-Zavaleta2, Ihosvany Rodríguez Pérez1
1Departamento de Fisiología, Biofísica y Neurociencias, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Mexico City, Mexico.
Frontiers in molecular neuroscience
|March 16, 2026
概括
在条状神经元中,对大麻素受体1 (CB1) 和G蛋白结合受体55 (GPR55) 异构体的顺序激活可增强GABA释放和运动行为. 这种效果是由初始CB1受体激活后异构化增加的介导.
科学领域:
- 神经科学是一个神经科学.
- 分子药理学分子药理学
- 神经药理学神经药理学
背景情况:
- 众所周知,大麻素受体1 (CB1) 和G蛋白结合受体55 (GPR55) 受体在条状神经元中形成异构体.
- 这些CB1-GPR55异构体对GABA释放和运动控制的功能影响在很大程度上仍未被探索.
研究的目的:
- 为了研究CB1-GPR55异构体在状神经元上的存在和功能.
- 评估这些异构体对cAMP积累,GABA释放和运动行为的影响.
- 探索顺序受体激活对异构化和信号传递的影响.
主要方法:
- 近距离结合试验 (PLA) 与P物质免疫光结合,检测大鼠条体和黑色物质中的异构体.
- 卡因酸病变,以评估条纹输入的作用.
- 测量cAMP积累和GABA从内格尔终端释放的测量.
- 免疫沉试验证实了突触体中异构体的形成.
- 行为测试涉及内部激动剂的管理,以评估运动活动.
主要成果:
- 在背上条纹体和黑质体中确定了CB1-GPR55异构体,在条纹性病变后的存在减少.
- 与单独激活GPR55相比,由GPR55 (CB1→GPR55) 随后的CB1序列激活显著增加了cAMP积累和GABA释放.
- 这种序列激活也导致了突触体中CB1/GPR55异构的增加,以及增强的运动行为 (反侧转).
- 无论是同时激活还是反向顺序激活 (GPR55→CB1),都没有产生类似的效果.
结论:
- CB1-GPR55异构体存在于状神经元终端上.
- 序列激活CB1R,其次是GPR55,增强了cAMP积累,GABA释放和运动行为.
- 这种增强是由初始CB1受体激活诱导的CB1/GPR55异构化增加的介导.
相关概念视频
Activation and Inactivation of G Proteins
12.2K
Heterotrimeric G proteins are guanine nucleotide-binding proteins. As the name suggests, heterotrimeric G proteins are composed of three subunits: alpha, beta, and gamma. They remain GDP-bound or GTP-bound inside the cells and switch between inactive/active states. The Gα subunit possesses the nucleotide-binding pocket that binds guanine nucleotides and switches between GDP or GTP-bound states. In contrast, the Gꞵ and Gγ subunits are always bound together with high...
12.2K
GPCRs Regulate Adenylyl Cylase Activity
8.1K
Some GPCRs transmit signals through adenylyl cyclase (AC), a transmembrane enzyme. AC helps synthesize second messenger cyclic adenosine monophosphate (cAMP). AC catalyzes cyclization reaction and converts ATP to cAMP by releasing a pyrophosphate. The pyrophosphate is further hydrolyzed to phosphate by the enzyme pyrophosphatase, which drives cAMP synthesis to completion. However, cAMP is rapidly degraded to 5′ AMP by the enzymes phosphodiesterase (PDE), preventing overstimulation of...
8.1K
G-Protein Gated Ion Channels
6.7K
GPCRs are primarily responsible for our sense of smell, taste, and vision. The binding of a sensory stimulus activates GPCR to stimulate effector proteins, many of which are ion channels in the sensory organs. GPCRs modulate the opening and closing of the target ion channels either directly by binding them, or by releasing second messengers that activate these channels. As ions move across the membrane, the membrane potential is altered, which induces an appropriate response.
Sensory...
Sensory...
6.7K
GPCR Desensitization
8.6K
G protein-coupled receptor (GPCR) signaling plays a crucial role in cell functioning. GPCR desensitization is an equally essential process. It allows cells to respond to changing environments and regain sensitivity to new stimuli while preventing unnecessary stimulation when no longer needed. Prolonged exposure to stimuli leads to GPCR desensitization. It involves blocking the receptors from binding and activating additional G proteins. This inhibits activation of downstream effectors, thereby...
8.6K
Ligand-Gated Ion Channel Receptor: Gating Mechanism
4.6K
Ligand-gated ion channels are transmembrane proteins that play a vital role in intercellular communication and functions of the nervous system. They allow the influx of ions across the membrane once the neurotransmitter binds, allowing the subsequent transmission of electrical excitation across the neurons. Other ligand-gated ion channels, like the γ-aminobutyric acid (GABA) receptor, permit anions like chloride into the cells on the binding of the GABA molecule. Their entry into the cell...
4.6K
G Protein-coupled Receptors
19.0K
G Protein-Coupled Receptors or GPCRs are membrane-bound receptors that transiently associate with heterotrimeric G proteins and induce an appropriate response to sensory stimuli such as light, odors, hormones, cytokines, or neurotransmitters.
GPCRs are also called heptahelical, 7TM, or serpentine receptors, and consist of seven (H1-H7) transmembrane alpha-helices that span the bilayer to form a cylindrical core. The transmembrane helices are connected by three extracellular loops and three...
GPCRs are also called heptahelical, 7TM, or serpentine receptors, and consist of seven (H1-H7) transmembrane alpha-helices that span the bilayer to form a cylindrical core. The transmembrane helices are connected by three extracellular loops and three...
19.0K


