Regional hypothermia inhibits spinal cord somatosensory-evoked potentials without neural damage in uninjured rats.
Both the therapeutic effects of regional hypothermia (RH) and somatosensory-evoked potentials (SSEP) have been intensively studied; however, the in vivo relationship between the two remains unknown. The primary focus of the current study was to investigate the impact of RH on SSEP in uninjured rats, as well as the neural safety of RH on neuronal health. An epidural perfusion model was used to keep local temperature steady by adjusting perfusion speed at 30°C, 26°C, 22°C, and 18°C for 30 min, respectively. Total hypothermic duration lasted up to 3 h. Neural signals were recorded at the end of each hypothermic period, as well as before cooling and after spontaneous rewarming. In addition, the Basso, Beattie, and Bresnahan (BBB) Locomotor Rating Scale was used to evaluate the effects of RH pre- and post-operative, combined with hematoxylin and eosin (H&E) and Fluoro-Jade C (FJC) staining. The results showed a marked declining trend in SSEP amplitude, as well as a significant prolongation in latency only during profound hypothermia (18°C). The BBB scale remained consistent at 21 throughout the entire process, signifying that no motor function injury was caused by RH. In addition, H&E and FJC staining did not show obvious histological injury. These findings firmly support the conclusion that RH, specifically profound RH, inhibits spinal cord SSEP in both amplitude and latency without neural damage in uninjured rats.
Department of Neurosurgery, School of Medicine, Second Military Medical University (Shanghai) , Jinling Hospital, Nanjing, Jiangsu Province, People's Republic of China.
Ning
N
Li
Lei
L
Tian
Wei
W
Wu
Huchen
H
Lu
Yuan
Y
Zhou
Xiaoyu
X
Xu
Xiangsheng
X
Zhang
Huilin
H
Cheng
Lihua
L
Zhang
D000818:Animals; D005073:Evoked Potentials, Somatosensory / Q000502:physiology*; D007036:Hypothermia, Induced; D008297:Male; D009474:Neurons / Q000502:physiology; D051381:Rats; D017207:Rats, Sprague-Dawley; D013116:Spinal Cord / Q000502:physiology*; D013119:Spinal Cord Injuries / Q000503:physiopathology