Biological Pacemaker Research
EurekAlert! notes that scientists continue to make progress towards replacing artificial pacemakers with biological equivalents: "Our study offers positive and direct evidence in living models that bioengineered cells can replace the electronic pacemaker. Our hope is to one day replace electronic pacemakers in people ... In the current study, the researchers delivered a gene encoding a bioengineered cell-surface protein to heart muscle cells of pigs. This protein mimics the combined action of several proteins called HCN ion channels, which play a critical role in maintaining a normal, evenly paced heartbeat. ... through gene expression, normal muscle cells of the heart were converted into pacemaker cells [in a matter of days] by a process called transdifferentiation. Studies done two weeks after the injections showed the new [pacemaker cells] were able to take over pacemaking function."
Link: http://www.eurekalert.org/pub_releases/2006-08/uocd-udr082106.php