Rotarod Performance test
Encyclopedia
The Rotarod Performance test is a performance test
based on a rotating rod with forced motor activity being applied , usually by a rodent
. The Rotarod Performance test measures parameters such as riding time (seconds) or endurance
. Some of the functions of the Rotarod Performance test include evaluating balance and coordination of the subjects; especially in testing the effect of experimental drug
s.
, coordination
, physical condition, and motor-planning. The speed of the rotarod is mechanically driven, and may either be held constant, or accelerated.
A human analog to rotarod test might be "log rolling" competitions, where an individual must maintain balance on a log floating in the water that rotates with even minimal torque
s applied by the contestant. Hamster
, gerbil
, and mouse
owners may have observed this principal in action when an animal climbs on the outer top of its wheel
, instead of inside of it. The main difference with the rotarod test, is that the rotation of the cylinder in experiments is usually mechanically driven.
(length of time) that can be used for statistical purposes to quantify the effects of differents drugs, conditions, and procedures. This test does not use subjective judgments of ability, and inter-rater reliability
will be virtually perfect. Inter-laboratory reliability will only be achieved if the various parameters (size of cylinder, speed of cylinder, composition material of surface, and amount of practice/training given the animal) are also replicated. The experiment is also very replicable from lab to lab (ibid). Moreover, these parameters may be adjusted variously to optimize the statistical separation of different conditions. For instance, alcohol
effects on mice become less apparent when the speed is increased .
Because of concern for impairment in human motor behavior from the use of prescription medications, the rotarod test is frequently used in early stages of drug development
to screen-out drugs that might later cause impairment in human driving, etc., that might not be detected epidemiologically
in the human population for a very long time.
The test may be useful as a sensitive indicator of trauma induced by brain injury
to laboratory rat
s.
Alcohol markedly impairs mouse performance in the rotarod test. Research using the rotarod test with various chemical agonist
s and antagonists may help scientists determine which components of neuron
s mediate the effects of chemicals. Genetic knock-outs and other manipulations, may also determine the genes most responsible for maintaining mammalian balance and coordination . Comparing the performance of different animals with specific brain lesions helps scientists map which structures are critical for maintaining balance.
Performance testing
In software engineering, performance testing is in general testing performed to determine how a system performs in terms of responsiveness and stability under a particular workload...
based on a rotating rod with forced motor activity being applied , usually by a rodent
Rodent
Rodentia is an order of mammals also known as rodents, characterised by two continuously growing incisors in the upper and lower jaws which must be kept short by gnawing....
. The Rotarod Performance test measures parameters such as riding time (seconds) or endurance
Endurance
Endurance is the ability for a human or animal to exert itself and remain active for a long period of time, as well as its ability to resist, withstand, recover from, and have immunity to trauma, wounds, or fatigue. In humans, it is usually used in aerobic or anaerobic exercise...
. Some of the functions of the Rotarod Performance test include evaluating balance and coordination of the subjects; especially in testing the effect of experimental drug
Experimental drug
An experimental drug is a substance that has been tested in a laboratory and has got approval from regulatory authorities to be tested on people. In the United States, the body responsible for approval is the U.S. Food and Drug Administration...
s.
Rationale
Basically, the test involves a rodent being placed on a horizontally oriented, rotating cylinder (rod) suspended above a cage floor, (not high enough to injure the animal, but high enough to induce avoidance of fall). Rodents naturally try to stay on the rotating cylinder, or rotarod, and avoid falling to the ground. The length of time that a given animal stays on this rotating rod is a measure of their balanceBalance
- Equipment :* Balance beam, a piece of gymnastics apparatus.* Balance board, a piece of training equipment.* Balancing machine, a machine that balances mechanical rotating parts to lessen vibration.* Balance wheel, a watch component....
, coordination
Motor coordination
thumb|right|Motor coordination is shown in this animated sequence by [[Eadweard Muybridge]] of himself throwing a diskMotor coordination is the combination of body movements created with the kinematic and kinetic parameters that result in intended actions. Such movements usually smoothly and...
, physical condition, and motor-planning. The speed of the rotarod is mechanically driven, and may either be held constant, or accelerated.
A human analog to rotarod test might be "log rolling" competitions, where an individual must maintain balance on a log floating in the water that rotates with even minimal torque
Torque
Torque, moment or moment of force , is the tendency of a force to rotate an object about an axis, fulcrum, or pivot. Just as a force is a push or a pull, a torque can be thought of as a twist....
s applied by the contestant. Hamster
Hamster
Hamsters are rodents belonging to the subfamily Cricetinae. The subfamily contains about 25 species, classified in six or seven genera....
, gerbil
Gerbil
A gerbil is a small mammal of the order Rodentia. Once known simply as "desert rats", the gerbil subfamily includes about 110 species of African, Indian, and Asian rodents, including sand rats and jirds, all of which are adapted to arid habitats...
, and mouse
Mouse
A mouse is a small mammal belonging to the order of rodents. The best known mouse species is the common house mouse . It is also a popular pet. In some places, certain kinds of field mice are also common. This rodent is eaten by large birds such as hawks and eagles...
owners may have observed this principal in action when an animal climbs on the outer top of its wheel
Hamster wheel
Most wheels are constructed of steel or plastic, both with advantages and problems. Solid plastic wheels are safer for some types of pets, such as hamsters and hedgehogs, because the space between rungs is solid and the animal's feet or legs cannot get stuck between rungs, an injury risk in steel...
, instead of inside of it. The main difference with the rotarod test, is that the rotation of the cylinder in experiments is usually mechanically driven.
Scientific use
The advantage of this test is that it creates a discretely measurable, continuous variableVariable
Variable may refer to:* Variable , a logical set of attributes* Variable , a symbol that represents a quantity in an algebraic expression....
(length of time) that can be used for statistical purposes to quantify the effects of differents drugs, conditions, and procedures. This test does not use subjective judgments of ability, and inter-rater reliability
Reliability
In general, reliability is the ability of a person or system to perform and maintain its functions in routine circumstances, as well as hostile or unexpected circumstances.Reliability may refer to:...
will be virtually perfect. Inter-laboratory reliability will only be achieved if the various parameters (size of cylinder, speed of cylinder, composition material of surface, and amount of practice/training given the animal) are also replicated. The experiment is also very replicable from lab to lab (ibid). Moreover, these parameters may be adjusted variously to optimize the statistical separation of different conditions. For instance, alcohol
Alcohol
In chemistry, an alcohol is an organic compound in which the hydroxy functional group is bound to a carbon atom. In particular, this carbon center should be saturated, having single bonds to three other atoms....
effects on mice become less apparent when the speed is increased .
Because of concern for impairment in human motor behavior from the use of prescription medications, the rotarod test is frequently used in early stages of drug development
Drug development
Drug development is a blanket term used to define the process of bringing a new drug to the market once a lead compound has been identified through the process of drug discovery...
to screen-out drugs that might later cause impairment in human driving, etc., that might not be detected epidemiologically
Epidemiology
Epidemiology is the study of health-event, health-characteristic, or health-determinant patterns in a population. It is the cornerstone method of public health research, and helps inform policy decisions and evidence-based medicine by identifying risk factors for disease and targets for preventive...
in the human population for a very long time.
The test may be useful as a sensitive indicator of trauma induced by brain injury
Brain injury
A brain injury is any injury occurring in the brain of a living organism. Brain injuries can be classified along several dimensions. Primary and secondary brain injury are ways to classify the injury processes that occur in brain injury, while focal and diffuse brain injury are ways to classify...
to laboratory rat
Laboratory rat
A laboratory rat is a rat of the species Rattus norvegicus which is bred and kept for scientific research. Laboratory rats have served as an important animal model for research in psychology, medicine, and other fields.- Origins :...
s.
Alcohol markedly impairs mouse performance in the rotarod test. Research using the rotarod test with various chemical agonist
Agonist
An agonist is a chemical that binds to a receptor of a cell and triggers a response by that cell. Agonists often mimic the action of a naturally occurring substance...
s and antagonists may help scientists determine which components of neuron
Neuron
A neuron is an electrically excitable cell that processes and transmits information by electrical and chemical signaling. Chemical signaling occurs via synapses, specialized connections with other cells. Neurons connect to each other to form networks. Neurons are the core components of the nervous...
s mediate the effects of chemicals. Genetic knock-outs and other manipulations, may also determine the genes most responsible for maintaining mammalian balance and coordination . Comparing the performance of different animals with specific brain lesions helps scientists map which structures are critical for maintaining balance.