The overall goal of this procedure is to quantify an effective exercise activity for ischemic stroke prevention in rats using a positioning running wheel. This method can help answer key questions in the small medicine field regarding stroke prevention. The main advantage of this technique is that it shows a highly effective running wheel system that can be used for ischemic stroke prevention in rats.
The implications of this technique enhance the effectiveness of stroke prevention because the middle cerebral artery encroaching results show our proposed PRW system outperformed the traditional treadmill system. Though this method can provide insight into stroke prevention, it can also be applied to other disease models such as Alzheimer's disease. Demonstrating the procedure will be Ling-Yu Tang and Chung-Ham Wang, technicians from our laboratory.
Begin by attaining a transparent acrylic running wheel, 55 centimeters in diameter, and 15 centimeters in width. Cut a quarter circle opening into one side of the running wheel to serve as an entrance and exit for the rats. Then, place a layer of high-friction rubber track on the inside of the acrylic wheel.
Next, connect an iron rod with bearings to the running wheel. Then, place two acrylic triangular columns on either side of the running wheel to act as the support frame. Use screws to attach a one millimeter thick semi-circular transparent acrylic sheet to the external sides of the two triangular columns.
Ensure that the acrylic sheets are approximately three centimeters away from each side of the running wheel. Use this sheet to position the infrared sensors;to do this, drill a hole in each acrylic sheet at every 45 degree increment in advance. Then, create holes that are the same size as the infrared sensors.
To operate the running wheel, use a Brushless DC Motor and a Motor Driver. Mount a rubber disk 10 centimeters in diameter onto the motor's central axis. Using the iron frame and springs to support the motor, connect the rubber disk from the motor's central axis to the outer side of the running wheel.
Next, use a microcontroller to rotate the rubber disk, and observe the rotation of the running wheel. Afterwards, mount four infrared emitters on one side, and the corresponding four infrared receivers on the opposite side sequentially between zero degrees and 135 degrees. Finally, connect four pairs of infrared sensors that are mounted in both acrylic sheets to the microcontroller's general pins using single core cables, in order to form the position-running wheel system.
Three days before starting the three week training exercise, allow the rat to become familiar with the running environment by manually operating the running wheel. During manually-operated training, gradually accelerate the running speed until the rat is unable to keep pace. Once this occurs, decrease the speed until the rat regains a steady running pace, and then gradually increase the speed again until the rat reaches 20 meters per minute.
Three days later, begin the three week exercise training by pressing the start button on the microcontroller each week to execute a training model where the rat runs for 20 meters per minute for 30 minutes during week one, 30 meters per minute for 30 minutes during week two, and 30 meters per minute for 60 minutes during week three. Maintain the rat at a steady state of running between zero degrees and 135 degrees, which is defined as the effective exercise area. Begin by evaluating behavioral performance by neurological severity scores in all stroke rats the day before surgery, as well as daily for seven days after the surgery.
Next, measure the limb-strength of the rat using an inclined plane. To do this, place the rat on an inclined climbing apparatus on a daily basis, and acclimatize the rat to the apparatus and the testing conditions one week before testing. During testing, place the rat at the top of the apparatus in a direction where the body axis aligns with the longitudinal axis of the inclined plane.
Ensure that the rat stays along the slope of the rubber-ribbed surface of the inclined plane, which should be set at an angle of 25 degrees. Increase the angle dynamically using a ball screw connected to a stepper motor to determine the maximal angle at which the rat can hold onto the plane. Gradually increase the angle of the inclined plane until the rat fails to hold on, and then detect a sliding down event.
Finally, have two naive observers independently examine and score all the behavioral tests. This study presented a scientific approach for quantifying effective exercise activity in stroke prevention training, and used neurological severity scores, or M-N-S-S, to verify the proposed method. These results show significant variation among all the exercise and the control groups, indicating that exercise benefits stroke prevention.
The PRW group provides the lowest score among the exercise groups, demonstrating a superior neuro-protective mechanism to the other training systems. Additionally, the PRW group acquires a much smaller infarct volume than the control group, and ranks the lowest among all the exercise groups, validating the prominent effect of PRW on stroke prevention. What's this technique can be done in sixteen hours if it is performed properly.
While attending this procedure, it's important to remember to rely and follow results and indicator to actually detail the rates, time, and position. Following this procedure, other methods, like a traditional motorized running wheel, can be performed in order to answer additional questions about stable learning. After its development, this technique paved the way for researchers in the field of exercise physiology to explore preventative medicine in rats.
After watching this video, you should have a good understanding of how to construct a highly effective running wheel system for ischemic stroke prevention in rats.