Central inspiratory influence on abdominal expiratory nerve activity.
Central inspiratory influence on abdominal expiratory nerve activity.
复制标题
吸气中枢对腹部呼气神经活动的影响。
DOI：
10.1152/jappl.1988.65.4.1647
复制
发表时间：
1988
期刊：
影响因子：
--
通讯作者：
BartlettJr,D
中科院分区：
文献类型：
--
作者：
Fregosi,RF;BartlettJr,D
我们的目的是确定腹部呼气神经放电的强度是否受前一次吸气膈神经放电强度的制约，而不受机械和化学传入的影响。在去大脑、瘫痪、迷走神经切断伴双侧气胸的猫中，我们记录了高氧常碳酸血症时的膈神经和腹部神经(颅髂腹下神经，L1)的活动。我们通过在中央吸气期(75微A，20-50赫兹，0.2ms脉冲)刺激切断的喉上神经(SLN)中央端来减少单周期的膈神经放电的持续时间和强度(即积分峰值高度)。吸气提前终止持续减少呼气持续时间(TE)和腹部呼气神经活动(积分神经图面积)，但TE的平均减少幅度远小于腹神经活动的减少(14%对51%)。刺激切断的迷走神经中心端也产生了类似的结果，我们在一只猫身上观察到了自发的吸气提前终止。高氧性高碳酸血症时刺激SLN可引起更多不同的反应，通常需要较高的刺激频率才能中止吸气。呼气时刺激SLN(或迷走神经)会持续增加腹部呼气神经的活动。我们推测，这种易化反应在吸气时被门控，从而允许吸气条件效应在随后的呼气中得以表达。
Our purpose was to determine whether the intensity of abdominal expiratory nerve discharge is conditioned by the intensity of the preceding inspiratory phrenic discharge, independent of mechanical and chemical afferent influences. In decerebrate, paralyzed, vagotomized cats with bilateral pneumothoraxes, we recorded phrenic and abdominal (cranial iliohypogastric nerve, L1) nerve activities at hyperoxic normocapnia. We reduced the duration and intensity (i.e., integrated peak height) of phrenic nerve discharge for single cycles by stimulating the cut central end of the superior laryngeal nerve (SLN) during the central inspiratory phase (75 microA, 20-50 Hz, 0.2-ms pulse). Premature termination of inspiration consistently reduced expiratory duration (TE) and abdominal expiratory nerve activity (area of integrated neurogram), but the average reduction in TE was much less than the reduction in abdominal nerve activity (14 vs. 51%). Stimulation of the cut central end of the vagus nerve yielded similar results, as did spontaneous premature terminations of inspiration, which we observed in one cat. SLN stimulation during hyperoxic hypercapnia resulted in more variable responses, and higher stimulation frequencies were usually required to abort inspiration. SLN (or vagal) stimulation during expiration consistently increased abdominal expiratory nerve activity. We speculate that this facilitatory response is gated during inspiration, thereby allowing the inspiratory conditioning effect on the subsequent expiration to be expressed.(ABSTRACT TRUNCATED AT 250 WORDS)