Platelet-activating factor modulates cardiorespiratory responses in the conscious rat.
Platelet-activating factor modulates cardiorespiratory responses in the conscious rat.
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血小板激活因子调节清醒大鼠的心肺反应。
DOI：
10.1152/ajpregu.1998.275.2.r604
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发表时间：
1998
期刊：
影响因子：
--
通讯作者：
Torres,JE
中科院分区：
文献类型：
--
作者：
Gozal,D;Holt,GA;Graff,GR;Torres,JE
血小板活化因子受体(PAFR)的激活与神经元兴奋性的增加有关。我们推测PAF可能在心肺控制中起作用。在不受束缚的成年大鼠的背尾部脑干内微量注射一种长效的PAF类似物(MC-PAF，1μg in 1μL)，可引起明显的每分钟通气量(V·e)增加，主要是由于潮气量增加，并伴有呼吸性碱中毒、心率加快和动脉血压下降。这样的心血管和呼吸效应在给药后没有发生，无论是载体还是非活性类似物Lyso-PAF。当动物同时给予突触前PAF受体拮抗剂BN-52021或重组PAF乙酰水解酶时，这种作用被阻断。为了确定PAF在高碳酸血症和低氧呼吸中的相对贡献，在BN-52021的1μL的1μL中进行微量注射，或在另一种载体(CO，1μL)中进行微量注射。BN-52021对含5%二氧化碳的高碳酸血症模型无影响。而BN-52021组仅从118.7±6.9m l/m in增加到137.3±8.9m l/m in(CO：BN-52021，P<；0.001)。我们的结论是，在常氧状态下，脑干背尾PAFR的激活具有明显的心脏兴奋作用，在清醒大鼠对低氧的反应中起着重要的调节作用。
Platelet-activating factor receptor (PAFR) activation is associated with increases in neuronal excitability. We hypothesized that PAF may play a role in cardiorespiratory control. Ventilatory responses to microinjection of a long-acting PAF analog (mc-PAF, 1 μg in 1 μl) within the dorsocaudal brain stem were measured in unrestrained adult rats.mc-PAF elicited significant minute ventilation (V˙e) enhancements that were primarily due to tidal volume increases and were accompanied by respiratory alkalosis, heart rate increase, and reduction of arterial blood pressure. Such cardiovascular and respiratory effects did not occur after administration of either vehicle or the inactive analog lyso-PAF. The effect was blocked when animals were coadministered the presynaptic PAFR antagonist BN-52021 or recombinant PAF acetyl hydrolase. To determine the relative contribution of PAF to hypercapnic and hypoxic ventilation, microinjections were performed in additional animals with either vehicle (CO, 1 μl) or with 5 μg in 1 μl of BN-52021. Hypercapnic challenges with 5% CO2were unaffected by BN-52021. In contrast, although 10% O2breathing increased V˙efrom 120.4 ± 7.5 to 204.6 ± 11.4 ml/min in CO, after BN-52021, V˙eincreased only from 118.7 ± 6.9 to 137.3 ± 8.9 ml/min (CO vs. BN-52021,P< 0.001). We conclude that PAFR activation in the dorsocaudal brain stem exerts significant cardioventilatory effects during normoxia and appears to play an important modulatory role in the V˙eresponse to hypoxia in conscious rats.