MODELING OF SIDS IN NEONATAL SWINE

用新生猪作为婴儿猝死综合征的动物模型 （SIDS），我们将研究（使用急性和慢性制剂）： 1)出生后迷走神经对心脏的支配差异， 交感神经节后运动神经元; 2）心脏 心律失常和选择性内脏传入刺激的作用， 小岛屿发展中国家的病因，3）不同组合的影响， 心脏的自主神经支配对存活率的影响。 此外，慢性 动物，无论是假手术或去神经，将在 不同的条件，包括诸如饲养、温度 变化或缺氧。 这些去神经研究将允许 确定神经支配的重要性。 结果 实验诱导的交感神经和/或迷走神经的偏侧性 优势将验证平衡的神经支配的重要性， 心 在急性准备中，我们还将检查 去神经：1）室颤阈值和2） 对内脏传入刺激的反应，例如，心肺， J受体和化学受体。 最后，检查产后成熟度 心脏的自主调节，因此， 易受心律失常的影响，我们将获得运动神经元， 腹外侧核模糊，以确定：1）他们的变化 活动模式随年龄的变化，2）他们对传入输入的反应。和 3)他们的诱发反应是否与年龄有关 这些实验 还将提供有关心脏作用的必要信息， 以及记录新生猪的适用性 作为这种疾病的动物模型。 慢性动物将 在无菌操作条件下制备;血管通路端口将 用于血液采样和压力测量，而细导丝 将电极插入隔膜中，用于监测 呼吸功能;将通过针电极记录EKG。 急性实验将在Saffan麻醉下进行。 的 上述慢性和急性实验应提供急需的 关于改变自主调节的重要性的信息 心脏在婴儿猝死综合征病因学中的作用

Using neonatal swine as our animal model of sudden infant death syndrome (SIDS), we will investigate (using both acute and chronic preparations): 1) postnatal differences in innervation of the heart by vagal and postganglionic sympathetic motoneurons, 2) the role of cardiac arrhythmias and the effects of selected visceral afferent stimulation in the etiology of SIDS, 3) the effects of different combinations of autonomic denervation of the heart on survival. In addition, chronic animals, either sham operated or denervated, will be studied under different conditions including such stresses as feeding, temperature changes or hypoxia. These denervation studies will allow the determination of the importance of innervation postnatally. The results of the experimentally induced laterality of sympathetic and/or vagal dominance will verify the importance of balanced innervation of the heart. In the acute preparation we will also examine the effects of denervation on: 1) the ventricular fibrillation threshold and 2) responses to stimulation of visceral afferents, e.g., cardiopulmonary, J-receptor and chemoreceptor. Finally, to examine postnatal maturation of autonomic regulation of the heart and, therefore, of times of greatest susceptibility to arrhythmias, we will obtain motoneurons in the ventrolateral nucleus ambiguous in order to determine: 1) their changing pattern of activity with age, 2) their responses to afferent inputs. and 3) whether their evoked responses are age-related. These experiments will also supply the needed information concerning the role of cardiac arrhythmias in SIDS as well as document the suitability of neonatal swine as an animal model for this disease. The chronic animals will be prepared under sterile operating conditions; vascular access ports will be implanted for blood sampling and pressure measurements while fine wire electrodes will be inserted into the diaphragm for monitoring of respiratory function; the EKG will be recorded from needle electrodes. Acute experiments will be performed under Saffan anesthesia. The aforementioned chronic and acute experiments should supply much needed information regarding the importance of changing autonomic regulation of the heart in the etiology of SIDS.