The Neuroscience and Metabolic Phenotyping Core is pleased to offer new surgical procedures as part of its growing repertoire of services.

• Surgical models for stroke studies (MCAO and BCAS)
• EEG monitoring for sleep and epilepsy studies
• Cannula implantation for drug delivery studies
• Standard perfusion and dissection of select brain areas, and blood collection

MCAO
The middle cerebral artery occlusion (MCAO) is a procedure that is used to model ischemic stroke in humans. MCAO is a procedure achieved by insertion of a surgical intraluminal monofilament into the middle cerebral artery (MCA), which results in a focal cerebral injury in the MCA territory due to the obstruction of blood flow. A subsequent brain infarction in the MCA territory results. This technique can be used to model permanent or transient occlusion, and does not require craniotomy. To evaluate the extent of infarct, brain slices can be stained with 2,3,5-triphenyltetrazolium chloride (TTC). To assess the functional consequences of focal cerebral injury, a five-point neurological deficit score can be employed (0, no deficit; 1, failure to extend right paw; 2, circling to the right; 3, falling to the right; and 4, unable to walk spontaneously) and evaluated in a blinded fashion. In addition, a series of behavioural tests for motor and cognition can be included as well.

BCAS
Vascular Dementia is a progressive disease caused by reduced blood flow to the brain and is a predominant form of dementia after Alzheimer’s disease in the elderly. The widely accepted and a popular animal model to study vascular dementia is the bilateral common carotid artery stenosis (BCAS) procedure. BCAS is achieved by spiralling a microcoil around both left and the right common carotid artery, which compresses the artery resulting in decreased cerebral blood flow (CBF). The selection of the inner diameter of the microcoil may influence the degree of brain damage. The extent of the decreased CBF is measured by laser Doppler velocimetry, and the resultant behaviour can be characterised by a series of behavioural tests for motor and cognition.

ECoG or Surface EEG
Surface Electroencephalography (EEG) or electrocorticogram is an electrophysiological monitoring method to record electrical activity of the brain at the surface of the scalp using large subdural electrodes. The subdural macro electrodes are implanted such that they are in contact with the subdural region and anchored in the skull. This is a widely used animal model to study various brain related activities, such as sleep staging, anxiety, depression. The time duration for the recording of the signals depends on the nature of the study.

Cannula implantation
Implantable cannulas permit continuous access to the venous system for either intravenous substance administration or blood withdrawal. Cannulas, when implanted into the cerebral ventricles, can also be used to bypass the blood brain barrier, allowing drugs to be delivered directly into the brain. Cannula implantations are often used in animals undergoing drug addiction studies, for easy delivery of the test compound during the operant tests.

Perfusion/Dissection
Standard perfusion services, with whole brain harvesting, using saline and fix, is being offered. The saline and fix will have to be provided by the user. We also are able to carry out whole blood collection from the thoracic cavity during the perfusion procedure. Various brain areas from fresh or fixed brain tissues can be dissected. This includes the cerebellum, brainstem, superior/inferior colliculus, thalamus, amygdala, hippocampus, striatum, frontal cortex and olfactory bulb.

Service Charges

For more information and to discuss details of the experimental design, please contact us.
Please note: Prices are in SGD and subject to change without notice.