Recording Neural Activity of Unfolded Hippocampal Tissue Using Penetrating Microelectrode Array

Abstract

Source: Zhang, M., et al. Neural Activity Propagation in an Unfolded Hippocampal Preparation with a Penetrating Micro-electrode Array. J. Vis. Exp. (2015).

This video demonstrates the procedure to set up a recording chamber with a penetrating microelectrode array (PMEA) to capture neural signals from an unfolded hippocampus. This method allows us to study the speed and direction of propagation of neural activity within the unfolded hippocampus in vitro.

Protocol

All procedures involving animal samples have been reviewed and approved by the appropriate animal ethical review.

1. Solutions for Surgery and Experimental Recording

1. Prepare a normal artificial cerebrospinal fluid (aCSF) buffer containing (mM) NaCl (sodium chloride) 124, KCl (potassium chloride) 3.75, KH₂PO₄ (potassium dihydrogen phosphate) 1.25, MgSO₄ (magnesium sulfate) 2, NaHCO₃ (sodium bicarbonate) 26, Dextrose 10, and CaCl₂ (calcium chloride) 2. Use this normal aCSF for tissue recovery after dissection and for the washing system at the beginning of the ....

Results

Figure 1. Experimental setup. (A) A plastic cover lid with screws is placed over the circuits to protect it against possible water damage. The recording chamber has both inlet and outlet tubes to carry the solution flow. A custom-made tissue anchor glued with .......

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
small paint brush	Lowe's	tem #: 105657 Model #: 90219	The one with the smallest size in a normal paint brush package
Fire polished glass help tool	N/A	N/A	This tool was fire polished and made from the regular Pasteur glass pipettes.
Custom made glass needle	N/A	N/A	This tool was fire polished and made from the regular Pasteur glass pipettes.
Custom made glass tool with a metal wire loop	N/A	N/A	This tool was fire polished and made from the regular Pasteur glass pipettes with a reshaped metal wire loop.
Custom made glass solution dropper	N/A	N/A	This tool was made from the regular Pasteur glass pipettes with its tips cut and a rubber head attached with the cut end.
Custom made tissue anchor	N/A	N/A	Nylon fiber mesh was glued on a insulated copper wire ring. The tissue anchor was hold by an micromanipulator.
Custom fabricated microelectrode array	N/A	N/A	More detail about the array please refer to Kibler, et al, 2011.
Custom made filter and amplifiers circuits for the array	N/A	N/A	More detail about the array please refer to Kibler, et al, 2011.
Data acquisition processor 3400a	Microstar Laboratories	N/A	This is a complete data acquisition system with A/D converter.