Imagine facing a stressful situation – maybe a thunderstorm quickly approaching or a surprise encounter on a hiking trail. Your body gears up, heart racing, senses heightened. Part of that healthy stress response often includes a subtle rise in core body temperature, preparing you for action.
For individuals with spinal cord injury (SCI), this natural response can be dramatically altered. SCI severely impacts the autonomic nervous system, which controls involuntary body functions like heart rate, blood pressure, and digestion. This disruption can lead to serious conditions like autonomic dysreflexia, where the body overreacts dangerously to stimuli.
Despite these widespread autonomic issues, how SCI affects the body's ability to control temperature, especially during stress, has been largely overlooked. Our latest preprint addresses this gap, revealing in rats how SCI affects crucial temperature-related stress responses.
Female and male rats were implanted with a small transmitter that measured activity and core temperature. Two weeks later, rats received T8 contusion SCI or sham laminectomy surgery.
Next, we assessed body temperature across the day in rats prior to and after SCI (or sham) surgery (Fig. 1). Prior to surgery, both male and female rats exhibit expected daily rhythms in core temperature, with higher temperatures during the active (dark) phase. We noted that handling elicited a stress response, including increased activity and body temperature. In sham-surgery rats, this stress-induced hyperthermia is maintained immediately after surgery. In contrast, SCI rats lack stress-elicited hyperthermia in the acute phase after SCI. This SCI-driven loss of stress-induced hyperthermia occurs in both female and male rats.
