内源性一氧化碳参与呼吸节律调节

本文旨在探讨内源性一氧化碳（carbon monoxide,CO）对呼吸节律的调节作用。采用新生Sprague—Dawley大鼠,制备离体延髓脑片标本,分别灌流CO、血红素氧合酶（heme oxygenase,HO）底物高铁血红素（hemin）和HO抑制剂ZnPP-9,观察舌下神经根呼吸样传出放电节律的变化。实验分为5组：单纯人工脑脊液（artificial cerebrospinal fluid,ACSF）对照组、ZnPP-9组、外源性CO组、Hemin组和ZnPP-9＋Hemin组。结果如下：在ZnPP-9组,舌下神经根节律性放电频率（discharge frequency,DF）增快（P〈0．05）;在外源性CO组,舌下神经根节律性DF减慢（P〈0.05）;在Hemin组和ZnPP-9＋Hemin组,舌下神经根节律性DF增快（P〈0．05）。结果表明,内源性CO对呼吸节律可能具有调节作用。

Involvement of endogenous carbon monoxide in regulation of respiratory rhythm in vitro

The aim of the present study was to investigate the effect of endogenous carbon monoxide (CO) on respiratory rhythm. The experiments were carried out on the medullary slices of newborn Sprague-Dawley rats. The rhythmic discharge frequency (DF) of hypoglossal rootlets was taken as an index of rhythmic respiratory activity. The slices of medulla oblongata were superfused with ZnPP-9 (inhibitor of heme oxygenase), CO and hemin (substrate of heme oxygenase), respectively, to observe their effects on respiratory rhythm. The preparations were divided into 5 groups: control group of artificial cerebrospinal fluid (ACSF), group of ZnPP-9, group of exogenous CO, group of hemin and group of ZnPP-9 + hemin. The results obtained were as follows. In ZnPP-9 group, the rhythmic DF of the hypoglossal rootlets was increased (P<0.05); while in exogenous CO group, it was decreased (P<0.05). In the groups of hemin and ZnPP-9 + hemin, the rhythmic DF of the hypoglossal rootlets was increased (P<0.05). It is suggested that endogenous CO may play an important role in the regulation of respiratory rhythm.