Imaging and Intracellular Analysis of Synaptic Plasticity in Spinal Dorsal Horn

1.电压敏感染料逆行染色背角I层边缘细胞电压反应成像，电压敏感染料注射丘脑或脑干，对I层投射神经元进行染色。在染料注射一周后，制作脊髓切片，并通过光学成像方法记录染色的细胞。成功地记录了背根电刺激诱发的电活动，在时间和空间上都具有高分辨率。动作电位和后电位清晰可见。我们目前正在研究LTP去增强的潜在机制。促肾上腺皮质激素释放因子（Corticotropin Releasing Factor，CRF）对脊髓背角可塑性诱导的调节我们已经寻找了调节脊髓背角可塑性诱导的物质，该物质在异常疼痛的诱导中起重要作用。我们已经发现，CRF双相调节诱导的强大变化的神经元兴奋在浅背角的光学成像。细胞外空间变化的光学分析：非突触传递的可能作用切片中的固有光信号（IOS）被认为可以反映细胞体积或细胞外空间。我们已经发现，协同转运蛋白和水通道在浅背角的IOS诱导中起主要作用。我们目前正在通过光学成像研究它们的调制器以及与体积变化相关的电活动变化。初级传入末梢突触前调制的光学分析：通过光学成像，我们能够记录突触前事件，并研究调制器。我们分析了氟烷和咖啡因以及香草酸受体激动剂的突触前作用。

1. Imaging of voltage response of marginal cell in the lamina I of the dorsal horn retrogradely stained with voltage-sensitive dye.Projection neurons in the lamina I were stained by voltage-sensitive dye that was injected in the thalamus or brain stem. After one week of the dye injection, slices of the spinal cord were made and the stained cells were recorded by an optical imaging method. The electrical activities evoked by dorsal root stimulation was successfully recorded optically with high resolution in both time and space. The action potentials and the after potentials were clearly observed. We are currently investigating the underlying mechanism of de-potentiation of LTP with this preparation.2. Modulation of dorsal horn plasticity induction by corticotropin releasing factor (CRF)We have searched substances that regulate induction of dorsal plasticity, which takes an important role in the induction of abnormal pain. We have found that CRF biphasically regulates the induction of robust changes in neuronal excitation in the superficial dorsal horn by optical imaging.3. Optical analysis of changes in extracellular space : Possible role for non-synaptic transmission.Intrinsic optical signals (IOS) in slice has been suggested to reflect cellular volume or extracellular space. We have revealed that cotransporters and water channels play the major role for the IOS induction in the superficial dorsal horn. We are currently investigating on their modulators and the changes in electrical activities associated with the volume changes by optical imaging.4. Optical analysis of presynaptic modulation at the primary afferent terminals.By optical imaging, we were able to record presynaptic events, and we investigated on the modulators. We analysed the presynaptic actions of halothane and caffeine as well as vanilloid receptor agoninsts.