an ">&ensp;</span>functional <span  title="" class="an ">&ensp;</span><span  title="BrainRegionP" class="an BrainRegionP">brainstem</span><span  title="" class="an ">&ensp;</span>preparations <span  title="" class="an ">&ensp;</span>of <span  title="" class="an ">&ensp;</span>mice <span  title="" class="an ">&ensp;</span><span  title="ProteinTrigger" class="an ProteinTrigger">containing</span><span  title="" class="an ">&ensp;</span>pre <span  title="" class="an ">&ensp;</span>Bötzinger <span  title="" cla