Expiratory (E) neurons in the caudal nucleus retroambigualis extend descending spinal axons to the lumbar and sacral spinal cord. Discharge rates of single E neurons were recorded to examine differences in activity of E neurons projecting to the lumbar or sacral spinal cord during fictive straining induced by distention of the colon with a balloon. Firing frequencies of E neurons with descending axons in the thoracic and lumbar spinal cord increased during the repetitive rise of rectum pressure, whereas those of E neurons with descending axons in the sacral spinal cord decreased. E neurons with descending axons in the thoracic/lumbar and sacral spinal cord exhibit different firing characteristics during the repetitive rise of rectum pressure when straining during defecation. The activity of abdominal nerves during fictive straining is in phase with changes in rectum pressure, but out of phase with the activity of E neurons.

中文翻译：

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猫虚构用力过程中髓质呼气神经元的放电特性。


疑后尾核中的呼气 (E) 神经元将下降的脊髓轴突延伸至腰部和骶部脊髓。记录单个 E 神经元的放电率，以检查在用气球扩张结肠引起的虚构紧张期间投射到腰部或骶脊髓的 E 神经元活性的差异。随着直肠压力的反复升高，胸腰段脊髓中下降轴突的E神经元的放电频率增加，而骶段脊髓中下降轴突的E神经元的放电频率则减少。当排便期间用力时，直肠压力重复升高时，胸/腰和骶脊髓中具有下降轴突的 E 神经元表现出不同的放电特征。虚构用力期间腹部神经的活动与直肠压力的变化同相，但与 E 神经元的活动异相。