论文部分内容阅读
背景:迄今为止呼吸节律的准确起源位置和其形成机制仍不清楚。作者以前的实验发现轻触压延髓腹侧表面舌下神经根部,家兔呼吸会立即停止。目的:观察在整体情况下,机械损毁家兔面神经后核内侧区对呼吸节律的影响。设计:随机对照实验。单位:昆明医学院生理教研室。材料:实验于2002-02/12在昆明医学院生理教研室进行。动物为实验用健康家兔54只,其中22只从延髓背侧面定位并机械损毁双侧面神经后核内侧区,18只从延髓腹侧面定位损毁,14只用于观察机械损毁面神经后核内侧区后血压和心率的变化。方法:分别暴露家兔延髓腹面侧和背面侧,切断双侧迷走神经,记录一侧膈神经放电作为呼吸指标,应用直径为0.8mm或0.4mm的不锈钢管损毁面神经后核内侧区,观察机械损毁对呼吸的影响。另取家兔14只,机械损毁双侧面神经后核内侧区,在机械损毁后1～3min家兔血压和心率的变化。主要观察指标:①机械损毁双侧面神经后核内侧区致呼吸节律改变。②膈神经放电数及呼吸频率。③②损毁后1～3min内血压和心率的变化。结果:54只家兔均进入结果分析。①从延髓腹侧面机械损毁双侧面神经后核内侧区致呼吸节律不可逆消失的总阳性率为67%(12/18),而从延髓背侧面机械损毁的总阳性率仅为14%(3/14)。②出现呼吸节律不可逆消失的所有家兔的膈神经节律性放电明显稀少,不规则。膈神经放电的吸气时程和呼气时程显著延长,当呼气时程极度延长时,呼吸节律消失,动物呼吸停止于呼气相。②部分机械损毁双侧面神经后核内侧区时,家兔(n=27)的呼吸仍存在,但立即表现出明显的呼吸抑制,呼吸频率显著变慢[(43.5±6.4)%,P<0.001],膈神经放电数显著减少[(42.0±3.7)%,P<0.001],膈神经放电的吸气时程和呼气时程均显著延长,但以呼气时程的延长极为显著。④对上述各损毁点做组织学检查,引起呼吸停止或呼吸明显减弱的位点均在面神经后核内侧区内。⑤在损毁后1～3min内,兔的心率和血压略有波动,变化幅度5%～7%,和正常值相比差异无显著性(P>0.05)。结论:面神经后核内侧区可能是呼吸节律产生的主要部位,而面神经后核内侧区中的呼吸相关神经元则可能是形成呼吸节律的重要组成部分。
Background: The exact origin and mechanism of respiratory rhythm so far remains unclear. The author’s previous experiments found that pressing the hypoglossal root of the ventral medulla oblongata, rabbit breathing will stop immediately. OBJECTIVE: To observe the effects of mechanical damage on the respiratory rhythm of the medial area of the posterior nucleus of the facial nerve in rabbits. Design: Randomized controlled experiment. Unit: Department of Physiology, Kunming Medical College. MATERIALS: The experiment was performed at Department of Physiology, Kunming Medical College from February to December 12, 2002. Fifty-four healthy rabbits were used as experimental animals. Twenty-two of them were located from the dorsal aspect of the medulla oblongata and mechanically damaged the medial region of the posterior nucleus of the bilateral facial nerve. Eighteen were located from the ventral medulla of the medulla oblongata and 14 were used to observe the medial posterior nucleus of the medulla oblongata After blood pressure and heart rate changes. Methods: Bilateral vagal nerves were severed by exposing the ventral and dorsal sides of rabbit medulla oblongata, and the phrenic nerve discharge was recorded as respiration index. The medial area of the posterior nucleus of the facial nerve was damaged by using a stainless steel tube with a diameter of 0.8mm or 0.4mm, and mechanical damage The effects of breathing. In addition, 14 rabbits were sacrificed to mechanically rupture the medial area of posterior nucleus of bilateral facial nerve. The changes of blood pressure and heart rate were observed in rabbits 1 ~ 3 minutes after mechanical rupture. MAIN OUTCOME MEASURES: ① Respiratory rhythm changes in medial area of bilateral posterior nucleus caused by mechanical damage. ② phrenic nerve discharge number and respiratory rate. ③ ② 1-3min after rupture of blood pressure and heart rate changes. Results: All 54 rabbits were involved in the result analysis. (1) The total positive rate of irreversible disappearance of respiratory rhythm was 67% (12/18) from medullary ventral medulla oblongata, while the total positive rate of mechanical damage from dorsal medulla oblongata was only 14% (3 / 14). ② appeared irreversible disappearance of respiratory rhythm of all rabbits phrenic rhythmic discharge was significantly less, irregular. Phrenic nerve discharge inspiratory time and expiratory duration significantly prolonged, when the expiratory duration is extremely prolonged, the respiratory rhythm disappears, animal breathing stopped in the expiratory phase. (2) Partial mechanical damage to the medial region of the posterior nucleus of the bilateral facial nerve resulted in the respiration of rabbits (n = 27), but immediately showed obvious respiratory depression and respiratory rate decreased significantly (43.5 ± 6.4%, P <0.001) ], The number of phrenic nerve discharge decreased significantly ([(42.0 ± 3.7)%, P <0.001]. The inspiratory time and expiratory duration were significantly prolonged in phrenic nerve discharge, but the prolongation of expiratory time was extremely significant. ④ to do damage to each of the above-mentioned histological examination, caused by respiratory arrest or significant reduction of respiratory sites in the medial area of the posterior face of the nerve. ⑤ Within 1 ~ 3min after the rupture, the rabbit’s heart rate and blood pressure slightly fluctuated by 5% -7%, which showed no significant difference compared with the normal value (P> 0.05). CONCLUSIONS: The medial region of the posterior nucleus of the facial nerve may be the main site of respiratory rhythm, whereas the respiratory-related neurons in the medial region of the posterior facial nucleus may be an important component of respiratory rhythm.