Developmental changes in central respiratory rhythmogenesis

μ-阿片DAMGO减慢新生大鼠体外呼吸节律。然而，我们发现，DAMGO应用于动脉灌注原位制备的灌注液一致地诱导呼吸加快，呼气时间显著减少。迷走神经吸气后活动消失。这些结果表明，DAMGO在幼年大鼠中将呼吸模式从3相转换为2相，这与新生大鼠的反应不同。

A μ-opioid DAMGO slows down the respiratory rhythm in neonatal rats in vitro. However, we found that DAMGO applied to the perfusate of the arterially perfused in situ preparation consistently induces rapid breathing with remarkable reduction of expiratory time. The vagal post-inspiratory activity was obliterated. These results indicate that DAMGO switches the breathing pattern from 3-phase to 2-phase in juvenile rats, which is different from the response of neonates.