Dopamine Release in Rats with Occlusal Interferences are Psychiatric Stress

为了阐明咬合干扰与精神压力之间的关系，我们测量了咬合干扰大鼠前额叶皮层多巴胺的释放。前额叶皮层多巴胺能神经元系统活动的变化已被发现是焦虑等应激反应的一个指标。我们在实验中使用苯二氮卓类药物（地西泮）来证明多巴胺释放增加是否由精神压力引起。三个实验采用微透析法测量多巴胺释放。每组实验中，对照组6只，咬合干扰组6只。每次实验测量多巴胺释放水平：我们在实验1中测量喂食颗粒前后的多巴胺释放水平。实验2在大鼠喂丸前先腹腔注射安定。实验三在大鼠喂丸前给予生理盐水。实验1：仅咬合干扰组，喂食后多巴胺释放量明显增加。实验2：两组大鼠多巴胺释放量均未明显增加。实验3：仅咬合干扰组，喂食后多巴胺释放量明显增加。当大鼠被喂食时，多巴胺的释放量因咬合干扰而增加。地西泮抑制了这种增加，但生理盐水没有。这些结果在统计学上证明了咬合干扰与焦虑相关的精神压力。

We measured dopamine release from the prefrontal cortex of rats with occlusal interferences in order to clarify the relation between the occlusal interferences and psychiatric stress. Changes in the activity of the dopaminergic neuron system of the prefrontal cortex have been found to be an index of stress responses involved in anxiety and so on. We used benzodiazepine (diazepam) in this experiment to show whether increased dopamine release was caused by psychiatric stress.Dopamine release was measured using microdialysis in three experiments. In each experiment, a control group comprised 6 rats and an occlusal interference group comprised 6 rats. The level of dopamine release was measured for each experiment : We measured it before and after feeding pellets in experiment 1. Diazepam was intraperitoneally administered before the rats were fed pellets in experiment 2. Physiological saline was given to the rats before they were fed pellets in experiment 3.Experiment 1 : In the occlusal interference group only, the amount of dopamine release significantly increased after feeding. Experiment 2 : The amount of dopamine release did not significantly increase in either group. Experiment 3 : In the occlusal interference group only, the amount of dopamine release significantly increased after feeding.The amount of dopamine release increased by occlusal interference when rats had been fed. Diazepam suppressed this increase, but physiological saline did not. These results proved statistically that occlusal interferences related to psychiatric stress involved in anxiety.