RAT ROTAROD METHOD

Animals

Studies are conducted in adult male and female Sprague Dawley rats (Envigo) in an AAALAC-accredited facility with approval from an Institutional Animal Care and Use Committee, and implemented in accordance with the Guide for the Care and Use of Laboratory Animals 8th Edition (National Research Council, 2011) with standards set by the National Institutes of Health.

Experimental procedure

The rotarod test is widely used to assess motor deficits, coordination, and sedation in rats. In the rotarod test, appropriate group sizes are determined by power analysis. Male and female rats (n=8-10) are evaluated in separate cohorts. Dose-responses are investigated and a vehicle control group is included. The experimenter is blinded to the treatments, and dosing is performed by an independent experimenter.

The day before testing, rats are trained on the rotarod (AccuRotor EZ-Rod, Omnitech Electronics, Inc., Columbus, OH) for 3 training trials. Each trial on the rod is identical, with a 5 second ramp from 0 to 17 revolutions per minute (RPM) followed by a period of constant velocity at 17 RPM for up to 40 seconds (cut off) (Simmons et al., 2002). The next day, animals complete a baseline trial prior to dosing. The outcome measured is the latency to fall off the rotating rod. Animals that maintain posture and stay on the rod throughout the duration of the trial are given a score of 40 seconds. To proceed to the testing phase animals must achieve a score of 40 seconds during the baseline trial. Animals that meet the inclusion criterion are balanced across treatment groups based on body weight. Rotarod performance can be assessed at multiple times after asset administration.

This work was conducted by PsychoGenics Inc. (Paramus, NJ) in collaboration with PSPP, NINDS, NIH under contract # 75N95019D00026