多巴胺D3受体调节D2受体对cAMP和GABA在条形体末端的释放的影响-由Ca2+系统调节-卡尔莫杜林-CaMKII系统
Flor Selene Villalobos-Escobedo1, Rafael Jijón-Lorenzo1, José Arturo Avalos-Fuentes1
1Departamento de Fisiología, Biofísica y Neurociencias, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Mexico City, Mexico.
The European journal of neuroscience
|December 27, 2023
概括
多巴胺D3受体 (D3R) 增强多巴胺D2受体 (D2R) 对cAMP和GABA释放的作用. 这种相互作用是由calmodulin和CaMKII调节的,影响着条形状神经元的功能.
科学领域:
- 神经科学是一个神经科学.
- 神经药理学神经药理学
- 分子生物学分子生物学
背景情况:
- 多巴胺D2受体 (D2R) 在条形状神经元中表达,调节循环腺单酸盐 (cAMP) 积累和胺黄油酸 (GABA) 释放.
- 多巴胺D3受体 (D3R) 在状D2R表达神经元和状球体中发现,这表明存在潜在的功能相互作用.
研究的目的:
- 为了研究D2R和D3R在条形体末端的局部化.
- 为了确定D3R是否调节D2R对cAMP积累和GABA释放的影响.
- 探索calmodulin (CaM) 和CaM-激酶II (CaMKII) 在调节D2R-D3R相互作用中的作用.
主要方法:
- 免疫沉测定检测D2R-CaM和D3R-CaMKIIα相互作用.
- 测量福斯科林刺激的 [3H]cAMP 积累在的突触体中.
- 在白切片中测量高K+刺激的 [3H]GABA释放.
- 使用了昆皮醇 (D2R/D3R激动剂),欧菲奥波林A (CaM抑制剂) 和KN62 (CaMKIIα阻断剂).
主要成果:
- D2R与CaM免疫沉,这种相互作用通过ophiobolin A或K+脱极化减少,增强了对cAMP的D2R抑制.
- 在CaM抑制的突触体中,D3R激活增强了对cAMP的D2R抑制.
- D2R和D3R在来自状体的状突触体中结合在一起,起源于状体.
- CaMKIIα与D3R免疫降低,和KN62治疗强化了D3R对D2R对cAMP和GABA释放的影响的D3R增强.
结论:
- 多巴胺D3受体增强了多巴胺D2受体对cAMP积累和GABA释放在球末端的抑制作用.
- D2R和D3R之间的功能相互作用是CaM负调节的,CaMKIIα正调节的.
- 这些发现阐明了一个新的调节机制,用于多巴胺信号在条形形通路.
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