ADAPTATION TO REFLEX EFFECTS OF PROLONGED LUNG-INFLATION
ADAPTATION TO REFLEX EFFECTS OF PROLONGED LUNG-INFLATION
复制标题
DOI：
10.1152/jappl.1985.58.4.1360
复制
发表时间：
1985-01-01
影响因子：
3.3
通讯作者：
FISHMAN, AP
中科院分区：
文献类型：
--
作者：
GRIPPI, MA;PACK, AI;FISHMAN, AP
观察肺容量持续变化对吸气时程（TI）、呼气时程（TE）和膈神经电图的适应性反射效应。在6分钟的试验期间，对用戊巴比妥钠麻醉的镓胺麻痹的狗进行测试充气，同时动物不通气：功能残气量（FRC）下2分钟，气道压力升高下2分钟，FRC下2分钟。通过输注三（羟甲基）氨基甲烷使犬过度氧合，并保持动脉PCO2 [CO2分压]恒定。维持充盈对TI的影响极小。在返回FRC时，TI与先前通货膨胀的幅度成比例地延长。膨胀产生显着的延长TE，然后适应回膨胀前的值。返回FRC时，TE最初缩短至低于对照值。这种缩短随着先前肺膨胀的增加而增加。对于TI，恢复FRC后重新建立稳态值的时间不同（14.8 ± 1.5）。4.6 s）和TE（33.8 . ±. 12.7 s）。从吸气开始的固定时间的膈神经图的幅度及其斜率不随充气而变化。显然，呼吸时相持续时间不仅受到每个呼吸周期内的肺传入输入的影响，而且还受到先前迷走神经传入活动的影响，迷走神经传入活动以长但不同的时间常数参与中枢过程。控制TI的缓慢中枢过程的传入输入不被门控到呼吸周期的仅1个相位。
Adaptation to the reflex effects of sustained changes in lung volume on inspiratory duration (TI), expiratory duration (TE) and the phrenic neurogram was examined. Test inflations in gallamine-paralyzed dogs anesthetized with pentobarbital sodium were made during a 6-min trial while the animal was not ventilated: 2 min at functional residual capacity (FRC), 2 min at elevated airway pressure and 2 min back at FRC. The dogs were hyperoxygenated and arterial PCO2 [partial pressure of CO2] was kept constant by an infusion of tris(hydroxymethyl)aminomethane. The maintained inflations produced minimal changes in TI. On return to FRC, TI was prolonged in proportion to the magnitude of the prior inflation. Inflation produced marked prolongation of TE, which then adapted back toward preinflation values. On return to FRC, TE shortened initially to values below control. This shortening increased with greater prior lung inflations. The times to reestablish steady-state values upon return to FRC differed for TI (14.8 .+-. 4.6 s) and TE (33.8 .+-. 12.7 s). The magnitude of the phrenic neurogram at a fixed time from onset of inspiration and its slope were unchanged with inflation. Apparently, respiratory phase durations are influenced not only by pulmonary afferent input within each respiratory cycle but also by prior vagal afferent activity that engages central processes with long, although different, time constants. Afferent input to the slow central process controlling TI is not gated to only 1 phase of the respiratory cycle.