Imaging Brain Damage Induced by Cerebral Hypoxia-Ischemia in a Mouse Model

Abstract

Source: Ouyang, Y., et al. Simultaneous PET/MRI Imaging During Mouse Cerebral Hypoxia-ischemia. J. Vis. Exp. (2015)

This video demonstrates a technique to assess cerebral hypoxia injury via simultaneous positron-emission tomography (PET) and magnetic resonance imaging (MRI). An anesthetized mouse undergoes common carotid artery (CCA) ligation, reducing blood flow to one brain hemisphere and predisposing it to hypoxia-induced injury. PET and MRI imaging evaluate glucose metabolism and structural changes during hypoxia. MRI detects restricted water diffusion, while PET reveals reduced glucose uptake, indicating hypoxia-induced cellular stress and metabolic impairment.

Protocol

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

1. Unilateral Common Carotid Artery (CCA) Ligation

1. Prepare sterile field with sterilized surgical tools and materials positioned conveniently. Ensure heating pad is warmed to 37 °C with temperature probe placed securely on the pad. Be sure to use a sterile drape to cover the surgical site.
2. Anesthetize animal (isoflurane, 1-3% in air at 0.5-1 L/min), and place animal in a supine position with the tail facing away. Check anesthetization by pinching the toe - this should elicit no reaction if the animal....

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
Surgery
Surgical scissors	Roboz	RS-5852
Forceps	Roboz	RS-5237
Hartman mosquito forceps	Miltex	7-26
2x McPherson suturing forceps, 8.5 cm	Accurate Surgical & Scientific Instruments	4473	It is useful to reduce the opening width with a band on the forceps used to hold the carotid artery
6-0 silicone coated braided silk suture with 3/8 C-1 needle	Covidien Sofsilk	S-1172
Homeothermic blanket system	Harvard Apparatus	507220F
Super glue	(Generic)
Hypoxia
Flowmeter for O₂	Alicat Scientific	MC-500SCCM-D
Flometer for N₂	Alicat Scientific	MC-5SLPM-D
O₂ meter	MSA	Altair Pro
Imaging
7.05 Tesla MRI System	Bruker	BioSpec	20 cm inner bore diameter with gradient set. Paravision 5.1 software.
Volume Tx/Rx 1H Coil, 35mm ID	Bruker	T8100
PET system	(In-house)		4x24 LSO-PSAPD detectors,
10x10 LSO array per detector,
1.2mm crystal pitch and 14mm depth. 14 x 14 mm PSAPD. FOV: 60x35mm. 350-650 keV energy window. 16 ns timing window.
Vessel cannulation Dumont forceps	Roboz	RS-4991
PE-10 polyethylene tubing	BD Intramedic	427401
Infusion pump	Braintree Scientific	BS-300
Animal monitoring & gating equipment	Small Animal Instruments Inc.	Model 1025	Only respiration monitoring used
Animal bed with temperature regulation	(In-house)