ss="an ">&ensp;</span>response <span  title="" class="an ">&ensp;</span>to <span  title="" class="an ">&ensp;</span><span  title="CAP" class="an CAP">MNS</span><span  title="" class="an ">&ensp;</span>Hz <span  title="" class="an ">&ensp;</span>ms <span  title="" class="an ">&ensp;</span>supramaximal <span  title="" class="an ">&ensp;</span>currents <span  title="" class="an ">&ensp;</span>Naloxone <span  title="" class="an ">&ensp;</span>micro <span  title="" class="an ">&ensp;</span>M <span  title="" clas