|MadSci Network: General Biology|
Yes it is true that you can make an animal's heart beat using electricity and it will work for any animal's heart. The reason for this is that our hearts beat naturally by passing small electric currents through the tissue each beat to make the muscle that the heart is made from contract in a synchronized manner, which results in a heart beat.
Most importantly though, the heart needs to be very fresh and the tissue still 'living' for this to work, a heart that has been removed from the body and stored on ice will only work for a few hours after the death of the animal. Therefore I do not think that you will have much luck in getting your caribou heart to contract in response to electricity now.
When the heart is working normally in the body electrical signals are generated in a node (the sino-atrial node) at the top of the heart and passed through a specialised conduction system around the heart, coordinating the contraction of the muscle. This pumps the blood in a coordinated manner to efficiently eject all the blood from the chambers of the heart on each beat. This natural rhythm of contraction stops shortly after the death of the animal. However if the heart is removed and set up in a special chamber and an external electrical pulse is applied it will continue to beat for several hours. However it is important that solution flows through the blood vessels that supply the heart muscle to keep the muscle cells 'alive' and working. The heart muscle has to be maintained artificially under the same conditions as it was in the body to continue to work. As you can see it is a fairly complex procedure to keep an animal's heart beating after its death and this is generally only done in the laboratory under controlled conditions to perform experiments on the beating heart.
Thank you for your question.
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