Restraint to Induce Stress in Mice and Rats.

Across all animal species, exposure to stressful conditions induces stress responses. One method to study the effects of stress using rodent models is the restraint stress procedure. Restraint stress has been used for decades to investigate changes in physiology, genetics, neurobiology, immunology, and other systems impacted by stress. Due to the ease of performing the procedure, low cost, and numerous modifications to scale for the intensity and duration of stress exposure, a vast literature of studies has used restraint stress in mice and rats. As one example, this study presents previously published data showing the impact of restraint stress in transgenic mice on plasma corticosterone levels and optogenetically-induced norepinephrine release. Acute restraint stress increased plasma corticosterone levels, yet this effect was blunted in mice following repeat restraint stress. However, stimulated norepinephrine release in the bed nucleus of the stria terminalis was increased only in the repeat restraint stress group. These data highlight important considerations of restraint parameters on dependent measures. Additional descriptions of restraint stress in rats are also included for comparison. Finally, the influence of the parameters of the restraint (e.g., acute vs. chronic) and characteristics of the animal subjects (strain, sex, age) are discussed.