高压氧对正常大鼠海马神经元结构的影响

Effect of hyperbaric oxygen on structure of hippocampus neurons in adult rats

目的 观察不同高压氧及停止高压氧处置后 2 0d大鼠海马神经元结构的变化。方法 将正常成年大鼠暴露于 2 .5ATA高压氧环境中 ,每日 1次 ,每次给氧 30min× 2 + 10min ,连续 1～ 3个疗程 (10次为1疗程 )。结果 高压氧 1疗程时海马组织内毛细血管与神经元结构未见明显变化 ,2疗程时部分线粒体稍肿胀 ,3疗程时线粒体进一步肿胀、嵴模糊 ,部分粗面内质网轻度扩张、脱颗粒 ,毛细血管扩张 ,停高压氧处置后 2 0d上述变化恢复正常。高压空气组结构无明显改变。结论 高压氧可引起海马组织毛细血管扩张与神经元超微结构损伤 ,这种变化主要与高氧有关 ,非高气压所致 ,而且是可逆的。

Objective To study the structural changes of hippocampus neuron in rats exposed to hyperbaric oxygen (HBO) in different courses and 20 d after the treatment. Methods Twenty seven adult SD rats were divided into normal control group ( n =3), HBO group ( n =12) in which the animals were given HBO (2.5 ATA) treatment for 1～3 course (HBO was given once a day with 30 min oxygen for twice and 10 min air at the interval as one treatment, 10 times of this treatment named as 1 course), and hyperbaric air (HBA) group ( n =12) in which the rats were undergone HBA treatment just as the same way of HBO group. Changes in the hippocampus of rats were observed with light and electron microscope. Results After 1 course of HBO treatment, there was no change in hippocampus capillaries and neurons. After 2 courses, partial mitochondria in neurons became swelling and after 3 courses, the mitochondria swelled further with blurred crista and rough surfaced endoplasmic reticulum dilated slightly and lost its granules. The capillaries in the hippocampus expanded. The changes mentioned above returned to normal in the 20th d after the treatment. No changes of these were found in rats with hyperbaric air treatment. Conclusion HBO can lead to the expansion of capillaries and ultrastructural changes of neurons in the hippocampus. These changes are mainly due to HBO but not hyperbaric air and they are reversible.