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View Full Version : Interesting study. Python protein increases heart size during digestion.


Clay Davenport
03-04-2005, 04:15 AM
Paris - 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 which 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 percent, allowing a far bigger volume of blood to be delivered to the digestive organs.

Hicks' team worked with three groups of Burmese pythons, which fasted for 28 days before being given a tasty rat dinner comprising 25 percent 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 percent within 48 hours.

The study appears on Thursday in Nature, the British weekly science journal. - AFP

Link (http://www.iol.co.za/index.php?set_id=1&click_id=31&art_id=qw1109788740351S525)

Clay Davenport
03-05-2005, 06:34 AM
LONDON - When a Burmese python swallows a tasty rat dinner, the reptile makes new heart muscle to help digest the big meal, biologists have found.

The predator has a special protein to expand its cardiac muscle, researchers say.

James Hicks of the University of California and his team found that by increasing the mass of its heart cavity by 40 per cent, the python can deliver more blood to its digestive organs.

The team studied three groups of Burmese pythons:

Group 1 fasted for 28 days.
The second were digesting rats that equalled 25 per cent of their body mass.
The final group was examined 28 days after a feast.

Within 48 hours of eating, the ventricular muscle mass swelled up, a change that was fully reversible, the researchers found.

The change in heart size was linked to increased synthesis of a cardiac contractile protein called heavy-chain myosin.

It can take weeks for the human form of heavy-chain myosin to expand from regular and intense exercise, but in snakes it happens much more quickly.

In Thursday's issue of the journal Nature, the researchers suggest the Burmese python "could provide an attractive model for investigating the fundamental mechanisms that lead to cardiac remodelling and ventricular growth."

Link (http://www.cbc.ca/story/science/national/2005/03/03/python-heart050303.html)

cthulhu77
03-05-2005, 09:30 AM
that is way too cool !!! Fascinating!
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