Haxhiu M A, Cherniack N S, van Lunteren E
Department of Medicine, Case Western Reserve University Cleveland, Ohio 44106.
J Appl Physiol (1985). 1990 Dec;69(6):1981-6. doi: 10.1152/jappl.1990.69.6.1981.
The central effects of tachykinins (substance P, neurokinin A, and neurokinin B) on the distribution of the motor activity to rib cage and abdominal expiratory muscles were studied in anesthetized tracheotomized spontaneously breathing dogs and cats. Intracisternal application of substance P (11 dogs) in doses of 10(-5) to 10(-4) M caused diaphragm electrical activity to change insignificantly from 19.3 +/- 1.9 to 24.8 +/- 3.2 units (P greater than 0.05), produced a moderate increase of triangularis sterni activity from 12.6 +/- 2.2 to 19.2 +/- 2.2 units (P less than 0.05), and stimulated a large increase of transversus abdominis activity from 9.4 +/- 2.7 to 28.5 +/- 2.6 units (P less than 0.01). Comparable effects were seen with similar doses of neurokinin A (8 dogs) and neurokinin B (3 dogs) administered intracisternally. Local application of substance P to the ventral medullary surface (5 dogs and 4 cats) also caused expiratory muscle activity to increase more than diaphragm activity, and in addition transversus abdominis activity increased to a larger extent than triangularis sterni activity. Furthermore, administration of the substance P antagonist [D-Pro2,D-Trp7,9]-SP to the ventral medullary surface decreased respiratory motor output, with expiratory muscles activity being attenuated to a greater extent than diaphragm activity. Application of neurotensin and N-methyl-D-asparate to the ventral surface of the medulla produced responses similar to those observed as a result of central administration of tachykinin peptides. The results suggest that 1) mammalian tachykinins are involved in the regulation of thoracic and abdominal expiratory muscle activity, 2) these muscles manifest substantial differences in their electrical responses to excitatory neuropeptides acting centrally, and 3) inputs from modulatory neurons located in this vicinity of the ventral medullary surface seem to be distributed unevenly to different expiratory premotor and/or motoneurons.
在麻醉、气管切开且自主呼吸的犬和猫身上，研究了速激肽（P物质、神经激肽A和神经激肽B）对胸廓和腹部呼气肌运动活动分布的中枢效应。给11只犬脑池内注射剂量为10(-5)至10(-4)M的P物质，膈电活动从19.3±1.9单位轻微变化至24.8±3.2单位（P>0.05），胸骨三角肌活动适度增加，从12.6±2.2单位增至19.2±2.2单位（P<0.05），腹横肌活动大幅增加，从9.4±2.7单位增至28.5±2.6单位（P<0.01）。给8只犬脑池内注射相似剂量的神经激肽A以及3只犬脑池内注射神经激肽B也观察到类似效应。将P物质局部应用于延髓腹侧面（5只犬和4只猫），也导致呼气肌活动比膈活动增加更多，此外腹横肌活动比胸骨三角肌活动增加幅度更大。此外，将P物质拮抗剂[D-Pro2,D-Trp7,9]-SP应用于延髓腹侧面会降低呼吸运动输出，呼气肌活动比膈活动衰减程度更大。将神经降压素和N-甲基-D-天冬氨酸应用于延髓腹侧面产生的反应与中枢给予速激肽肽观察到的反应相似。结果表明：1）哺乳动物速激肽参与胸廓和腹部呼气肌活动的调节；2）这些肌肉对中枢作用的兴奋性神经肽的电反应存在显著差异；3）位于延髓腹侧面附近的调节神经元的输入似乎不均匀地分布到不同的呼气前运动神经元和/或运动神经元。
