Lipton J W, Davidson T L, Carvey P M, Weese-Mayer D E
Department of Pediatrics, Rush Medical College, Rush University, Chicago, IL 60612, USA.
Respir Physiol. 1996 Nov;106(2):161-9. doi: 10.1016/s0034-5687(96)00075-8.
The effects of prenatal (embryonic days 7-21) cocaine (30 mg/kg b.i.d., s.c.) exposure on postnatal respiratory and behavioral responsiveness to acute hypoxia were investigated in 5-day-old (P5) rat pups. Control and cocaine-exposed pups were subjected to 20 min of 0.21 FIO2 followed by 20 min of 0.08 FIO2. Although all pups demonstrated the characteristic biphasic response to hypoxia, cocaine-exposed pups exhibited a blunted, initial response in minute ventilation (p < 0.05) and inspiratory drive (p < 0.05) as compared with control pups who showed increases in these measures (p < 0.01 and p < 0.05, respectively). The consequence of this apparent blunted ventilatory response was reflected in blood gas data gathered after 20 min of 0.08 FIO2:PCO2 (p < 0.05) and base-excess (p < 0.05) were increased and HCO3- (p < 0.05) and SO2 (p < 0.01) were decreased relative to control pups. Cocaine-exposed pups also exhibited behavioral evidence of decreased struggling (p < 0.001) in response to the hypoxic challenge. These data in the rat confirm our previous findings of altered ventilatory responsiveness to inspired hypoxia in the rabbit and extend our observations of a decreased ability to successfully compensate and behaviorally arouse following prenatal cocaine-exposure, thus underscoring the potential vulnerability of infants so exposed.
研究了产前（胚胎期第7 - 21天）可卡因（30毫克/千克，皮下注射，每日两次）暴露对5日龄（P5）大鼠幼崽出生后呼吸及对急性低氧行为反应性的影响。将对照组和可卡因暴露组幼崽置于21%氧分压环境中20分钟，随后置于8%氧分压环境中20分钟。尽管所有幼崽对低氧均表现出典型的双相反应，但与对照组幼崽（这些指标分别增加，p < 0.01和p < 0.05）相比，可卡因暴露组幼崽在分钟通气量（p < 0.05）和吸气驱动力（p < 0.05）方面的初始反应减弱。这种明显减弱的通气反应的后果反映在8%氧分压环境中20分钟后收集的血气数据中：与对照组幼崽相比，二氧化碳分压（p < 0.05）和碱剩余（p < 0.05）增加，碳酸氢根（p < 0.05）和血氧饱和度（p < 0.01）降低。可卡因暴露组幼崽对低氧刺激的挣扎行为证据也减少（p < 0.001）。大鼠的这些数据证实了我们之前关于家兔对吸入性低氧通气反应性改变的发现，并扩展了我们对产前可卡因暴露后成功代偿和行为唤醒能力下降的观察结果，从而强调了此类暴露婴儿的潜在脆弱性。
