The Burmese python is able to boost the size of its heart chambers by half in order to help it digest a big meal, thanks to a remarkable protein that expands cardiac muscle, researchers say.
The reptile’s “extraordinarily rapid” increase in heart size enables it to cope with a 40-fold rise in metabolic rate during digestion, according to a team led by University of California biologist James Hicks.
The secret lies in genes that make proteins called heavy-chain myosin.
By flooding the heart muscle with these proteins, the serpent’s ventricles increase by 50%, allowing a far bigger volume of blood to be delivered to the digestive organs.
Hicks’s team worked with three groups of Burmese pythons, which fasted for 28 days before being given a tasty rat dinner comprising 25% of their body weight. The snakes then digested for the following four weeks.
Human beings also have heavy-chain myosin, but it takes regular and intense exercise to attaining higher levels of this protein in order to improve heart function.
In Burmese pythons, though, the ventricular muscle mass swells by 40% within 48 hours.
The study appears on Thursday in Nature, the British weekly science journal. — AFP