Activity Test – Porsolt forced swim

Activity Test – Porsolt Forced Swim Test: A Comprehensive Guide

Porsolt forced swim test, also known as the behavioral despair test, is a widely used preclinical screening tool for assessing antidepressant activity and depression-anxiety-like behavior in small laboratory animals. It is a validated and reliable method that can be performed in mice, rats, guinea pigs, and other small species.

Key Points:

  • Basics: The test involves subjecting an animal to a swimming session of fixed duration, usually 5-6 minutes, in a transparent cylinder filled with water. The animals tend to show mobility initially, but after a few minutes, they stop swimming and adopt a passive posture, characterized by immobility and floating behavior.
  • Rationale: The immobility response is postulated to reflect a state of behavioral despair or learned helplessness and is considered a predictive biomarker for antidepressant efficacy in humans. Therefore, drugs that can reduce the immobility time or increase the swimming activity of animals are considered potential antidepressants.
  • Protocol: The Porsolt forced swim test has a standardized protocol and is typically conducted in a quiet, controlled environment with minimal disruption. The animals are acclimatized to the testing environment beforehand and are exposed to the swim session only once during the experimental procedure.
  • Analysis: The primary measure of the Porsolt test is the immobility time, i.e., the duration in which the animal remains motionless. Other parameters, such as the latency to immobility or the active swimming time, can also provide additional insights into the behavioral profile of the animal.
  • Limitations: Although the test is widely used, it has been criticized for being non-specific and lacking face validity regarding the underlying neurobiology of depression. Furthermore, the test results can be influenced by several factors, such as age, sex, stress, circadian rhythms, and prior drug treatments, among others.

In conclusion, the Porsolt forced swim test is a valuable tool for assessing antidepressant activity and evaluating depression-like symptoms in preclinical animal models. Despite its limitations, it remains a widely used and accepted test in the field of neuroscience and drug development.