West D C, Thomson A M, Do K Q
Department of Visual Sciences, Institute of Ophthalomology, London, UK.
J Neurosci Methods. 1992 Jun;43(1):35-42. doi: 10.1016/0165-0270(92)90064-k.
These experiments combined electrophysiological recordings from hippocampal slices with application of drugs to and sampling of extracellular fluid from a restricted region of the slice using a push-pull cannula placed under the slice in an interface chamber. Stable and apparently normal extracellular and intracellular recordings could be obtained directly over the tip of the cannula and solutions changed without disturbing the recording. Relatively rapid effects (1-5 min) were observed when TTX, CNQX, or medium containing 50 mM K+ were applied via the cannula and recovery from these effects was achieved. In addition, effects were restricted to the immediate vicinity of the cannula; neurones recorded several hundred micrometers away were apparently unaffected. Samples of extracellular fluid obtained as minute fractions during the application of high K+ containing medium contained higher concentrations of GABA, aspartate and glutamate than control fractions but the same levels of other amino acids, e.g., isoleucine and leucine. With appropriate design of push-pull cannula and recording chamber, therefore, stable electrophysiological recordings can be combined with localized extracellular fluid sampling and rapid and localized application of test solutions in an interface slice chamber.
这些实验将海马切片的电生理记录与药物应用相结合，通过放置在界面腔室切片下方的推挽式套管对切片的受限区域进行细胞外液采样。可以直接在套管尖端上方获得稳定且明显正常的细胞外和细胞内记录，并且在不干扰记录的情况下更换溶液。当通过套管应用TTX、CNQX或含有50 mM K+的培养基时，观察到相对快速的效应（1-5分钟），并且从这些效应中恢复。此外，效应仅限于套管的紧邻区域；几百微米外记录的神经元显然未受影响。在应用含高K+培养基期间作为微量部分获得的细胞外液样本中，GABA、天冬氨酸和谷氨酸的浓度高于对照部分，但其他氨基酸（例如异亮氨酸和亮氨酸）的水平相同。因此，通过适当设计推挽式套管和记录腔室，可以在界面切片腔室中将稳定的电生理记录与局部细胞外液采样以及测试溶液的快速局部应用相结合。
