Control of bronchomotor tone during perinatal development in sheep.
Control of bronchomotor tone during perinatal development in sheep.
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绵羊围产期发育过程中支气管运动张力的控制。
DOI：
10.1152/jappl.1993.75.4.1486
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发表时间：
1993
期刊：
影响因子：
--
通讯作者：
Kinloch,LP
中科院分区：
文献类型：
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作者：
PerezFontan,JJ;Kinloch,LP
为了表征围产期成熟的胆碱能控制的气道，我们比较了双侧颈部迷走神经切断术和超大迷走神经刺激对气道阻力的7个早产儿（妊娠130-133天），11个足月新生儿，9个9周龄的羔羊麻醉与戊巴比妥。阻力在中心和外周气道之间分配，导管逆行放置在外周支气管中，胶囊附着在胸膜表面与胸膜下空气空间连通。早产儿和足月新生羔羊的中心和外周气道阻力以及9周龄羔羊的外周阻力在迷走神经切断术后降低，但仅在平均经肺压≤ 7.5 cmH 2 O时以小潮气量通气时才降低。迷走神经切断引起的中枢气道阻力的绝对变化小于迷走神经刺激。与此相反，迷走神经切断术和迷走神经刺激产生了类似的绝对变化，外周气道阻力，表明静息胆碱能外流优先分布到外周气道，即使在较早的年龄。阿托品可阻断迷走神经刺激对气道阻力的影响。我们的研究结果证明，一个休息支气管舒张音可以存在于中央和外周气道妊娠期前的绵羊。这种张力依赖于迷走神经中胆碱能纤维的活动，并且可以进行区域控制。
To characterize the perinatal maturation of the cholinergic control of the airways, we compared the effects of bilateral cervical vagotomy and supramaximal vagal stimulation on the airway resistances of 7 premature (130–133 days of gestation), 11 term newborn, and 9 9-wk-old lambs anesthetized with pentobarbital. Resistances were partitioned between central and peripheral airways with catheters placed retrogradely into peripheral bronchi and capsules attached to the pleural surface in communication with subpleural air spaces. The central and peripheral airway resistances of premature and term newborn lambs and the peripheral resistance of 9-wk-old lambs decreased after vagotomy but only when the lungs were ventilated with small tidal volumes at mean transpulmonary pressures < or = 7.5 cmH2O. Vagotomy caused smaller absolute changes in central airway resistance than vagal stimulation. In contrast, both vagotomy and vagal stimulation produced similar absolute changes in peripheral airway resistance, indicating that resting cholinergic outflow is preferentially distributed to the peripheral airways even at the earlier ages. The effects of vagal stimulation on airway resistance were prevented by atropine. Our results prove that a resting bronchomotor tone can be present in both central and peripheral airways before the term of gestation in sheep. This tone depends on the activity of cholinergic fibers in the vagus and can be regionally controlled.