pan  title="" class="an ">&ensp;</span>channels <span  title="" class="an ">&ensp;</span>slow <span  title="" class="an ">&ensp;</span>gating <span  title="" class="an ">&ensp;</span>and <span  title="" class="an ">&ensp;</span>fast <span  title="" class="an ">&ensp;</span>gating <span  title="" class="an ">&ensp;</span>were <span  title="" class="an ">&ensp;</span>observed <span  title="" class="an ">&ensp;</span>in <span  title="" class="an ">&ensp;</span>immature <span  title="" class="an ">&ensp;</span>