Hippocampal सर्किट हल्का घाव मस्तिष्क की चोट के बाद समारोह के बदलाव पर जांच
Summary
Hippocampal circuitry के लिए कार्यात्मक परिवर्तनों की जांच करने के लिए एक बहुआयामी दृष्टिकोण समझाया गया है. Electrophysiological तकनीकों के साथ चोट प्रोटोकॉल, व्यवहार परीक्षण और क्षेत्रीय विच्छेदन विधि के साथ वर्णित हैं. इन तकनीकों के संयोजन अन्य मस्तिष्क क्षेत्रों और वैज्ञानिक सवाल के लिए इसी तरह फैशन में लागू किया जा सकता है.
Abstract
Traumatic Brain Injury (TBI) afflicts more than 1.7 million people in the United States each year and even mild TBI can lead to persistent neurological impairments 1. Two pervasive and disabling symptoms experienced by TBI survivors, memory deficits and a reduction in seizure threshold, are thought to be mediated by TBI-induced hippocampal dysfunction 2,3. In order to demonstrate how altered hippocampal circuit function adversely affects behavior after TBI in mice, we employ lateral fluid percussion injury, a commonly used animal model of TBI that recreates many features of human TBI including neuronal cell loss, gliosis, and ionic perturbation 4-6.
Here we demonstrate a combinatorial method for investigating TBI-induced hippocampal dysfunction. Our approach incorporates multiple ex vivo physiological techniques together with animal behavior and biochemical analysis, in order to analyze post-TBI changes in the hippocampus. We begin with the experimental injury paradigm along with behavioral analysis to assess cognitive disability following TBI. Next, we feature three distinct ex vivo recording techniques: extracellular field potential recording, visualized whole-cell patch-clamping, and voltage sensitive dye recording. Finally, we demonstrate a method for regionally dissecting subregions of the hippocampus that can be useful for detailed analysis of neurochemical and metabolic alterations post-TBI.
These methods have been used to examine the alterations in hippocampal circuitry following TBI and to probe the opposing changes in network circuit function that occur in the dentate gyrus and CA1 subregions of the hippocampus (see Figure 1). The ability to analyze the post-TBI changes in each subregion is essential to understanding the underlying mechanisms contributing to TBI-induced behavioral and cognitive deficits.
The multi-faceted system outlined here allows investigators to push past characterization of phenomenology induced by a disease state (in this case TBI) and determine the mechanisms responsible for the observed pathology associated with TBI.
Protocol
Discussion
प्रत्येक ऊपर उल्लिखित तकनीक अंतर्निहित मनाया व्यवहार घाटे के कारण तंत्र का अधिक से अधिक समझ के लिए योगदान देता है. अद्वितीय प्रत्येक विधि से प्राप्त जानकारी के संयोजन से हम अधिक परिशुद्धता के साथ जैव…
Disclosures
The authors have nothing to disclose.
Acknowledgements
लेखकों के लिए अपने तकनीकी सहायता के लिए पूंजीपति इलियट धन्यवाद करना चाहते हैं. यह काम स्वास्थ्य R01HD059288 और R01NS069629 अनुदान के राष्ट्रीय संस्थान द्वारा वित्त पोषित किया गया था.
Materials
| Name of the equipment | Company | Catalogue number | Comments (optional) |
| Axopatch 200B amplifier | Molecular Devices | AXOPATCH 200B | Patch-clamp rig |
| Digidata 1322A digitizer | Molecular Devices | Patch-clamp rig | |
| MP-225 micromanipulator | Sutter | MP-225 | Patch-clamp rig |
| DMLFSA microscope | Leica | Patch-clamp rig | |
| Multiclamp 700B amplifier | Molecular Devices | MULTICLAMP 700B | Multipurpose (field) rig |
| Digidata 1440 digitizer | Molecular Devices | Multipurpos (field) rig | |
| MPC-200 micromanipulator | Sutter | MPC-200 | Multipurpose (field) rig |
| BX51WI microscope | Olympus | BX51WI | Multipurpose (field) rig |
| Axoclamp 900A amplifier | Molecular Devices | AXOCLAMP 900A | VSD rig |
| Digidata 1322 digitizer | Molecular Devices | VSD rig | |
| Redshirt CCD-SMQ camera | Redshirt | NCS01 | VSD rig |
| VT 1200S Vibratome | Leica | 14048142066 | |
| P-30 Electrode puller | Sutter | P-30/P | |
| cOmplete protease inhibitor | Roche | 11697498001 |
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