Animal models of depression

It is a common, long-lasting and diverse psychiatric syndrome that significantly affects a person's thoughts, behavior, feelings and sense of well-being.

Some of these symptoms may include sadness, anxiousness, emptiness, hopelessness, worry, helplessness, worthlessness, guilt, irritableness, hurt, or restlessness.

People experiencing depression may also lose interest in activities that once were pleasurable, experience loss of appetite, overeat, have problems concentrating, remembering details, making decisions, and may contemplate or attempt suicide.

Insomnia, excessive sleeping, fatigue, loss of energy, aches, pains, or digestive problems that are resistant to treatment may also be present.

Many animals lack self-consciousness, self-reflection, and consideration; moreover, hallmarks of the disorder such as depressed mood, low self-esteem or suicidality are hardly accessible in non-humans.

An ideal animal model offers an opportunity to understand molecular, genetic, and epigenetic factors that may lead to depression.

[25] Suitable animal models could provide a basis for understanding potential mechanisms of environmental and developmental factors of individual differences in stress reactivity and vulnerability to disorders.

Antidepressant screening tests provide only an end-point behavioral or physiological measure designed to assess the effect of the genetic, pharmacological, or environmental manipulation.

Animal research has been a successful way for experts to gain this knowledge and it continues to have positive impacts in the medical field and beyond.