UCI Lab Rats to Take Flight on Space Shuttle Project

Talk about leaving the rat race.

Twenty-two baby rats, the research subjects of a UC Irvine professor, will be launched into outer space today aboard the space shuttle Columbia, to float about in their cages in zero gravity for 17 days.

UCI’s Kenneth Baldwin, professor of physiology and biophysics, hopes to discern information from the muscles of baby rats in space that could help gravity-bound humans on Earth.

“The goal of our experiment is to find out how gravity influences how the muscles grow and function during critical stages of development,” said Baldwin, who arrived in Cape Canaveral, Fla., last week to oversee his rats preflight.

“In order to factor out the effects of gravity,” he said, “we subject them to micro-gravity.”

Baldwin’s rats will be free-falling with plenty of company. Called Neurolab, the mission’s Spacelab module will be housing dozens of rats, mice, fish, snails and crickets, all research subjects in coordinated experiments to study the nervous system in space. Seven astronauts will be their in-flight attendants.

Researchers back on the ground hope to learn information that will help future astronauts endure longer periods of weightlessness, such as aboard space stations or during a possible trip to Mars.

The Neurolab “is probably the most ambitious research package ever done in one project,” said Baldwin, who is assigned to the Mammalian Development Team, one of eight science teams for the mission.

Previous research on space missions has shown that in absence of gravity, muscles atrophy, he said.

Baldwin’s new research will explore what effect gravity has on the production and interplay of certain hormones and a protein within the muscle.

Myosin, the “motor protein” of the muscle, will be one of the elements under scrutiny. Scientists also will be looking at the rats’ production of insulin-like growth factor (IGF-1), the primary hormone that mediates muscle growth, he said.

Rats are an excellent animal model for such studies because they go through critical stages of development within just a few weeks, equivalent to a human growing from baby to adolescent, he said.

Baldwin’s rodents will be divided into two age groups--7 days and 14 days old at launch--to study a broader range of development. The younger group, numbering 16, will be divided, with half having normal thyroid function, and the others with hypothyroidism.

All six older animals will have normal thyroid glands. Because of space restrictions, Baldwin is not able to have an equal number of older rats with hypothyroidism, but after the space shuttle lands, he will receive muscle tissue from other rats being used in another experiment.

Three mother rats will accompany the babies, who will receive all of their nourishment through nursing.

Sending rats into space involves much more than loading wire cages into a spaceship.

“These are very sophisticated cages,” he said. Because there is no gravity, food and water must be delivered to the mother rats through special apparatus. There is a filtering system that captures animal waste so that it does not contaminate the air, he said.

While in space, the rats “will be free-falling in their cages,” Baldwin said. “It will look like they are swimming in the air.”

While the 22 baby rats and their mothers are orbiting, there will be two control groups of rats--all identically aged--in the ground lab at the Kennedy Space Center.

When the space shuttle lands, the real work begins, he said.

Baldwin’s project team--Gregory Adams, Sam McCue and Paul Bodell, all researchers from UCI--will euthanize the rats and dissect them. Some of the tissue samples will be scrutinized under the microscope while the majority will be frozen and later biochemically analyzed to study the expression of the genes.

The results could reveal important information about the muscle atrophy that all humans experience through aging, he said. “Space accentuates what we see in muscle atrophy on Earth,” he explained.

“If we understand how muscles are affected by space flight,” Baldwin said, “we may be able to able to find better ways of sustaining our muscle mass on Earth, so that people have better motor skills, strength and endurance as they age.”