nsp;</span>When <span  title="" class="an ">&ensp;</span>expressed <span  title="" class="an ">&ensp;</span>in <span  title="" class="an ">&ensp;</span>Xenopus <span  title="" class="an ">&ensp;</span>oocytes <span  title="" class="an ">&ensp;</span><span  title="CAP" class="an CAP">HCN</span><span  title="" class="an ">&ensp;</span>channels <span  title="" class="an ">&ensp;</span>activate <span  title="" class="an ">&ensp;</span>fold <span  title="" class="an ">&ensp;</span>more <span  title="" class="an 