Microdialysis of Interstitial Fluid from a Mouse Brain to Isolate Extracellular Proteins

Abstract

Source: Yamada, K. In Vivo Microdialysis Method to Collect Large Extracellular Proteins from Brain Interstitial Fluid with High-molecular Weight Cut-off Probes. J. Vis. Exp. (2018)

The video demonstrates the process of using a microdialysis probe to collect extracellular proteins from the interstitial fluid (ISF) of a mouse brain. A microdialysis probe, equipped with a high-molecular-weight cut-off semi-permeable membrane, is inserted into the brain of an anesthetized mouse via an implanted guide cannula. The probe, connected to pumps, allows a physiological buffer to perfuse the brain tissue and mix with the ISF. Proteins in the ISF diffuse across the semi-permeable membrane and are collected for analysis.

Protocol

All procedures involving animal models have been reviewed by the local institutional animal care committee and the JoVE veterinary review board.

1. Pre-surgical Procedure

1. Before starting surgery, wipe everything with 70% ethanol to maintain sterile conditions. Thermal support using a heating pad is recommended.
2. Anesthetize the mice by intraperitoneal injection of chloral hydrate (400 mg/kg). Confirm anesthetization by performing a toe pinch. Use of meloxicam SR at induction and buprenorphine upon recovery BID (bis in die, twice a day) for at least 24 h is recommended.

Results

Figure 1: Surgery setup and the construction of microdialysis circuits. (A) Set up a stereotaxic assembly for a guide implantation using a cap nut, a stereotaxic adaptor and a guide cannula. (B) Stereotaxic surgery to implant a gui.......

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
The Univentor 820 Microsampler	Univentor	8303002	Refrigerated fraction collector
Syringe pump	KD scientific	KDS-101
Roller pump	Eicom microdialysis	ERP-10
Raturn Stand-Alone System	BASi	MD-1409	Free-moving system
Dual species cage kit	BASi	CX-1600
AtmosLM Microdialysis probe (shaft length 8 mm, membrane length 2 mm)	Eicom microdialysis	PEP-8-02	Shaft length for a probe, a guide, a dumy probe and a stereotaxic adaptor should be identical.
Microdialysis guide (shaft length 8 mm)	Eicom microdialysis	PEG-8
Microdialysis dummy probe (shaft length 8 mm)	Eicom microdialysis	PED-8
Bone screw	BASi	MD-1310
Super bond C&B set	Sunmedical		Dental cement
Small animal Stereotaxic Instrument with digital display console	Kopf	Model 940	Stereotaxic apparatus
Mouse and neonatal rat adaptor	Stoelting	51625
Standard Ear Bars and Rubber Tips for Mouse Stereotaxic	Stoelting	51648
Albumin solution from bovine serum	Sigma	A7284-50ML	30% BSA solution
FEP tubing (70 cm)	Eicom microdialysis	JF-10-70	Internal volume = 0.5 µL/cm
Teflon tubing (50 cm)	Eicom microdialysis	JT-10-50	Internal volume = 0.08 µL/cm
Byton tube	Eicom microdialysis	JB-30
Intramedic luer stab adaptor 23G	BD	427565	Blunt end needle
Roller tube	Eicom microdialysis	RT-5S	Internal volume = 4 µL
Cap nut	Eicom microdialysis	AC-5
0.25 mL microcentrifuge tube with cap	QSP	503-Q	Tubes for fraction collector
Sterotaxic adaptor (shaft length 8 mm)	Eicom microdialysis	PESG-8
Connection needle	Eicom microdialysis	RTJ
Mouse animal collar	BASi	MD-1365
High Speed Rotary Micromotor kit	FOREDOM	K.1070	Drill
Picrotoxin	Sigma	P1675
Screw driver for bone screws
Scalpel
Cotton swab
Surgical clipper