In the context of an animal experiment, what are the common methods used to induce stress, and how do researchers assess the physiological and behavioral responses of animals to these stressors?
In general, there are several common methods used to induce stress in animal:
Physical stressors: These can include restraint, exposure to cold or heat, forced exercise, or delivery of mild electric shocks. Researchers monitor the animal's heart rate, blood pressure, hormone levels, and behavior during and after exposure to assess the stress response.
Psychological stressors: These include exposure to a predator or predator odor, social isolation, crowding, loud noises, or bright lights. Researchers look for changes in the animal's anxiety-like behaviors, as well as physiological changes.
Pharmacological stressors: Injecting drugs that cause neurotransmitter changes similar to those seen in stress, such as corticotropin releasing factor or yohimbine. The drugs' effects on physiology and behavior are measured.
Environmental stressors: Altering the housing environment, such as tilting cages, providing unstable flooring, or frequently changing cage mates. Stress levels are gauged by behavioral observation.
However, the animal kinds are important, for example among rodents (mice, rats):
- Physical stressors like restraint or electric foot shocks. stress hormones, heart rate, blood pressure, body temperature are measures. Look for anxiety behaviors like decreased exploration.
- Psychological stressors like predator odor, social defeat, crowded housing. Measure stress hormones, anxiety behaviors, depression-like behaviors.
- Pharmacological stressors like corticosterone injections or drugs that reduce neurotransmitters like serotonin. Assess the impact on physiology and depressive/anxiety behaviors.
Non-human primates or Dogs have different approaches
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