Physiological Tolerance and Brain Responses to Sustained Whole-Body Rotation in Mice

Sustained high-speed rotation can occur when the body becomes dynamically unconstrained, such as during aircraft ejection or high-altitude free fall, and may rapidly threaten survival. Studies of transient angular acceleration have established rotational loading as an important cause of traumatic brain injury. However, sustained rotation represents a different exposure condition, in which the prolonged motion at high angular velocity may reveal organ-specific differences in mechanical and physiological tolerance. The survival limits and organ-specific vulnerabilities under this condition remain poorly defined. To address this gap, we developed a mouse model of sustained whole-body rotation and established a 50% lethal load (LL ₅₀ ) curve across rotational speeds and exposure durations. Unexpectedly, overt traumatic brain injury was absent across survival outcomes and near-threshold survivors exhibited only transient disturbances of brain function. In contrast, fatal cases were characterized by pronounced pulmonary abnormalities, without comparable pathological involvement of other major organs. These findings establish the physiological tolerance limits of sustained whole-body rotation, demonstrate that this loading condition can produce lethal injury beyond classical neurotrauma, and highlight the need for whole-body evaluation in extreme rotational risk assessment.