Clinical studies have shown that hyperbaric oxygen therapy improves motor function in patients with spinal cord injury. In the present study, we explored the mechanisms associated with the recovery of neurological function after hyperbaric oxygen therapy in a rat model of spinal cord injury. We established an acute spinal cord injury model using a modiifcation of the free-falling object method, and treated the animals with oxygen at 0.2 MPa for 45 minutes, 4 hours after injury. The treatment was administered four times per day, for 3 days. Compared with model rats that did not receive the treatment, rats exposed to hyperbaric oxygen had fewer apoptotic cells in spinal cord tissue, lower expression levels of aquaporin 4/9 mRNA and protein, and more NF-200 positive nerve ifbers. Furthermore, they had smaller spinal cord cavities, rapid recovery of somatosensory and motor evoked potentials, and notably better recovery of hindlimb motor function than model rats. Our ifndings indicate that hyperbaric oxygen therapy reduces apop-tosis, downregulates aquaporin 4/9 mRNA and protein expression in injured spinal cord tissue, improves the local microenvironment for nerve regeneration, and protects and repairs the spinal cord after injury.

水通道蛋白3和水通道蛋白9在结肠黏膜的表达及意义

目的 探讨结肠黏膜水通道蛋白3(aquaporin,AQP3)和水通道蛋白9(aquaporin,AQP9)的表达与分布情况,并探讨其与便秘的关系.方法 先用免疫组织化学技术检测45例功能性便秘(functional constipation,FC)患者(试验组)和32例非便秘患者(对照组)结肠黏膜AQP3和AQP9的分布情况;然后用Western bloting半定量检测AQP3和AQP9,以β-actin作内参蛋白,两者与相应β-actin灰度值之比即为AQP3和AQP9的相对含量,将灰度比值作统计学分析.结果 AQP3主要分布在肠黏膜上皮细胞的基底膜,AQP9主要分布在黏膜腔面杯状细胞.右半结肠试验组AQP3含量高于对照组(P＜0.05),AQP9差异无统计学意义(P＞0.05),而左半结肠试验组AQP9低于对照组(P＜0.05),AQP3差异无统计学意义(P＞0.05).结论 AQP3在右半结肠高表达,而AQP9在左半结肠高表达;功能性便秘患者右半结肠AQP3增加,而左半结肠AQP9降低;AQP3和AQP9含量的增加或减少可能与便秘的发生发展有一定关系.