Role of the red nucleus on mastication, swallowing, feeding and drinking behavior

1.我们研究了损毁红核(RN)是否可以改变下颌的节律性运动。重复电刺激口面部运动皮质或岛叶皮质可引起有节奏性的下颌运动。在RN中外加电流造成的损伤被发现影响刺激口面部运动皮质所引起的下颌节律性运动。致伤后最大张口位与最小张口位之间的距离较小。相反，损伤RN并不影响刺激岛叶皮质所引起的下颌节律性运动。然后，将红藻氨酸(损伤组)或磷酸盐缓冲液(对照组)注入左侧RN。注射3天后，重复电刺激口面部运动皮质，诱发有节律性的颌骨运动。病变组最大张口位与最小张口位之间的距离小于对照组。这些结果表明，RN参与了刺激口面部运动皮质引起的颌骨运动的改变。我们研究了单侧RN损伤对咀嚼、进食和饮水的影响。左侧RN注射红藻氨酸(损伤组)或磷酸盐缓冲液(对照组)。在手术后第一天和第二天，损伤组的平均颗粒摄入量显著减少。损伤组术后食物外溢明显增加。病变组会抓起一个药丸放进嘴里，但有时他们会咬几口，然后把它洒出来。术后第一天，损伤组的平均水滴摄入量显著减少。我们的研究表明，RN损伤组不能很好地咀嚼食物，从而减少了食物的摄取。

1. We study whether the red nucleus (RN) lesion can modify rhythmic jaw movements. Rhythmic jaw movements were induced by repetitive electrical stimulation of the orofacial motor cortex or the insular cortex. Lesions made by applied electric current in the RN were found to influence the rhythmic jaw movements induced by stimulation of the orofacial motor cortex. The distance between the maximum and minimum jaw-opening positions was less after the lesions were induced. In contrast, lesions of the RN did not influence rhythmic jaw movements induced by stimulation of the insular cortex. Next, kainic acid (lesion group) or phosphate-buffered saline (control group) was injected into the left RN. Three days after injection, rhythmic jaw movements were induced by repetitive electrical stimulation of the orofacial motor cortex. The distance between the maximum and minimum jaw-opening positions in the lesion group was smaller than in the control group. These results suggest that the RN is involved in the modification of jaw movements induced by stimulation of the orofacial motor cortex.2. We have examined the effect of a unilateral lesion of the RN on mastication, feeding and drinking. Kainic acid (lesion group) or phosphate-buffered saline (control group) was injected into the left RN. The mean number of pellets ingested in the lesion group was significantly less on the first and second days after surgery. Spillage of food increased greatly in the lesion group after surgery. The lesion group would grasp a pellet and put it into their mouth, but they sometimes bit a pellet several times, then spilled it. The mean number of drops of water ingested by the lesion group was significantly reduced on the first day after surgery. Our study suggests that the RN lesion group can not masticate food well, and ingestion of food then decreases.