Abstract
Purpose :
To continuously observe the damage of primary visual cortex caused by the optic nerve crush (ONC) in Thy1-eYFP transgenic mice.
Methods :
The structure and function of the primary visual cortex of live mice were evaluated by two-photon microscopy (TPM) before and after the surgery of ONC (0d, 3d, 7d, 14d and 28d) respectively at the same area in same mice which based on the localization of cerebral pia blood vessels. And the non-ONC mice were also observed.
Results :
Thy1-eYFP transgenic mice were anesthetized with 5% isoflurane and fixed on the brain stereotactic injection device. And the anterior and posterior fontanelles were adjusted on the same sagittal line through the positioning needle measurement, so that the anterior fontanelle and posterior fontanelle were at the same level as far as possible. Using a shaving razor shave the hair from the back of the head (between the ears) up to the eyes. Apply the eye ointment and clean the skin using sterile cotton swabs with 75% ethanol. Lift the skin and incise the skin horizontally along the base of the head from neck to eye. Scrape the periosteum and use a high-speed dental drill with small diameter burr to outline a 3 mm diameter circle until the brain tissue were exposed but still with dura cover on. Clean the drilling site and avoid the bleeding. Then put a steriled coverslip on the cranial window. After 3 days cranial window surgery, optic nerve crush surgery was applied. Optic nerves were camped about 1mm behind the ball. This surgery was performed only on the left eyes. Anti-inflammatory drugs, antibacterial and aerodyne were given to mice at the first 3 day after cranial window surgery. And anti-inflammatory drugs and antibacterial were given to mice per 3 day.
The number and density of neurons and the number of dendritic spines decreased in V1 region, which mainly affected L2/L3 layer and L5 layer in ONC mice, when compared with the non-ONC mice. And the negative affect of ONC sustain till 28 days after ONC.
Conclusions :
It’s a successful live animal model of continuously observing the damage of primary visual cortex caused by ONC, which provides us a new way of observing visual cortex in animal with visual pathway injury.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.