Recording of Local Field Potential in Mouse Hippocampal-Entorhinal Cortex Slices

Abstract

Source: Whitebirch, A. C. Acute Mouse Brain Slicing to Investigate Spontaneous Hippocampal Network Activity. J. Vis. Exp. (2020)

The video demonstrates a procedure to record the local field potential (LFP) in mouse hippocampal-entorhinal cortex slices. Electrical stimulation is provided at the CA3 stratum radiatum of the hippocampus, which causes changes in the postsynaptic potential at the CA1 stratum pyramidale. The combined change in the membrane potential of CA1 neurons, termed the local field potential, is recorded.

Protocol

All procedures involving sample collection have been performed in accordance with the institute's IRB guidelines.

1. Transcardial perfusion

1. Suspend a 60 mL capacity syringe as a reservoir for sucrose cutting solution approximately 18 inches above the benchtop (e.g., using a three-pronged swivel clamp on a vertical post). Attach tubing to the bottom of the reservoir, run the tubing through a roller clamp, and connect the other end of the tube to a clean 20 G needle.
2. Fill the 60 mL reservoir with approximately 30 mL of chilled sucrose solution and direct a carbogen line into the sucrose reservoir to cont....

Results

Figure 1: Preparation of horizontal angled hippocampal-entorhinal cortex (HEC) slices. (A)(i) After extracting the brain, perform two coronal cuts with a razor blade to remove the posterior and anterior portions of the br.......

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
Acute brain slice incubation holder	NIH 3D Print Exchange	3DPX-001623	Designed by ChiaMing Lee, available at https://3dprint.nih.gov/discover/3dpx-001623
Adenosine 5′-triphosphate magnesium salt	Sigma Aldrich	A9187-500MG
Ag-Cl ground pellets	Warner	64-1309, (E205)
agar	Becton, Dickinson	214530-500g
ascorbic acid	Alfa Aesar	36237
beaker (250 mL)	Kimax	14000-250
beaker (400 mL)	Kimax	14000-400
biocytin	Sigma Aldrich	B4261
blender	Oster	BRLY07-B00-NP0
Bonn scissors, small	becton, Dickinson	14184-09
borosilicate glass capillaries with filament (O.D. 1.5 mm, I.D. 0.86 mm, length 10 cm)	Sutter Instruments	BF150-86-10HP	Fire polished capillaries are preferable.
calcium chloride solution (1 M)	G-Biosciences	R040
camera	Olympus	OLY-150
compressed carbogen gas (95% oxygen / 5% carbon dioxide)	Airgas	X02OX95C2003102
compressed oxygen	Airgas	OX 200
constant voltage isolated stimulator	Digitimer Ltd.	DS2A-Mk.II
coverslips (22x50 mm)	VWR	16004-314
cyanoacrylate adhesive	Krazy Glue	KG925	Ideally use the brush-on form for precision
data acquisition software	Axograph	N/A	Any equivalent software (e.g. pClamp) would work.
Dell Precision T1500 Tower Workstation Desktop	Dell	N/A	Catalog number will depend on specific computer - any computer will work as long as it can run electrophysiology acquisition software.
Digidata 1440A	Molecular Devices	1-2950-0367
digital timer	VWR	62344-641	4-channel Traceable timer
disposable absorbant pads	VWR	56616-018
dissector scissors	Fine Science Tools	14082-09
double-edge razor blades	Personna	BP9020
dual automatic temperature controller	Warner Instrument Corporation	TC-344B
dual-surface or laminar-flow optimized recording chamber	N/A	N/A	The chamber presented in this protocol is custom made. A commercial equivalent would be the RC-27L from Warner Instruments.
equipment rack	Automate Scientific	FR-EQ70"	A rack is not strictly necessary but useful for organizing electrophysiology
Ethylene glycol-bis(2-aminoethyiether)- N,N,N',N'-teetraacetic acid (EGTA)	Sigma Aldrich	324626-25GM
filter paper	Whatman	1004 070
fine scale	Mettler Toledo	XS204DR
Flaming/Brown micropipette puller	Sutter Instruments	P-97
glass petri dish (100 x 15 mm)	Corning	3160-101
glucose	Fisher Scientific	D16-1
Guanosine 5′-triphosphate sodium salt hydrate	Sigma Aldrich	G8877-250MG
ice buckets	Sigma Aldrich	BAM168072002-1EA
isoflurane vaporizer	General Anesthetic Services	Tec 3
lab tape	Fisher Scientific	15-901-10R
lens paper	Fisher Scientific	11-996
light source	Olympus	TH4-100
magnesium chloride solution (1 M)	Quality Biological	351-033-721EA
magnetic stir bars	Fisher Scientific	14-513-56	Catalog number will be dependent on the size of the stir bar.
micromanipulator	Luigs & Neumann	SM-5
micromanipulator (manual)	Scientifica	LBM-2000-00
microscope	Olympus	BX51WI
microspatula	Fine Science Tools	10089-11
monitor	Dell	2007FPb
MultiClamp 700B Microelectrode Amplifier	Molecular Devices	MULTICLAMP 700B	The MultiClamp 700B should include headstages, pipette holders, and a model cell.
N-(2-Hydroxyethyl)piperazine-N′-(2-ethanesulfonic acid), (HEPES)	Sigma Aldrich	H3375-25G
needle (20 gauge, 1.5 in length)	Becton, Dickinson	305176
nylon filament	YLI Wonder Invisible Thread	212-15-004	size 0.004. This cat. # is from Amazon.com
nylon mesh	Warner Instruments Corporation	64-0198
perstaltic pump	Harvard Apparatus	70-2027
Phosphocreatine di(tris) salt	Sigma Aldrich	P1937-1G
pipette holders	Molecular Devices	1-HL-U
platinum wire	World Precision	PT0203
polylactic acid (PLA) filament	Ultimaker	RAL 9010
potassium chloride	Sigma Aldrich	P3911-500G
potassium gluconate	Sigma Aldrich	1550001-200MG
potassium hydroxide	Sigma Aldrich	60377-1KG
razor blades	VWR	55411-050
roller clamp	World Precision Instruments	14041
scale	Mettler Toledo	PM2000
scalpel handle	Fine Science Tools	10004-13
slice harp	Warner	SHD-26GH/2
sodium bicarbonate	Fisher Chemical	S233-500
sodium chloride	Sigma Aldrich	S9888-1KG
sodium phosphate monobasic anhydrous	Fisher Chemical	S369-500
sodium pyruvate	Fisher Chemical	BP356-100
spatula	VWR	82027-520
spatula/spoon, large	VWR	470149-442
sterile scalpel blades	Feather	72044-10
stirrer / hot plate	Corning	6795-220
stopcock valves, 1-way	World Precision Instruments	14054
stopcock valves, 3-way	World Precision Instruments	14036
sucrose	Acros Organics	AC177142500
support for swivel clamps	Fisher Scientific	14-679Q
surgical scissors, sharp/blunt	Fine Science Tools	14001-12
syringe (1 mL)	Becton, Dickinson	309659
syringe (60 mL with Luer-Lok tip)	Becton, Dickinson	309653
three-pronged clamp	Fisher Scientific	05-769-8Q
tissue forceps, large	Fine Science Tools	11021-15
tissue forceps, small	Fine Science Tools	11023-10
transfer pipettes	Fisher Scientific	13-711-7M
tubing	Tygon	E-3603	ID 1/16 inch, OD 3/16 inch
tubing	Tygon	R-3603	ID 1/8 inch, OD 1/4 inch
vacuum grease	Dow Corning	14-635-5D
vibrating blade microtome	Leica	VT 1200S
vibration-dampening table with faraday cage	Micro-G / TMC-ametek	2536-516-4-30PE
volumetric flask (1 L)	Kimax	KIM-28014-1000
volumetric flask (2 L)	PYREX	65640-2000
warm water bath	VWR	1209