Biomedical Research
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MOSCOW,
CAPE CANAVERAL––Fifteen two-year-old Oriental newts and 80
snails were brought aboard the Russian space station Mir on May 18, to
resume neurological studies of the effects of weightlessness on anatomy
that were disrupted in February when eight newts died during their
return to earth aboard a cargo shuttle.
The newts and snails are to remain in orbit until August––if they endure that long. |
Photograph of Mir courtesy NASA |
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| Similar
work undertaken by the 16-day, $99 million “Neurolab” flight
of the NASA space shuttle Columbia during April and early May brought
mostly unplanned early deaths of the specimens. The casualties might
have contributed to NASA’s May 5 announcement that the Neurolab
would not fly a second time in August, as had been tentatively planned.
Reportedly taking more animals into space in one mission than ever previously orbited, Neuro-lab lifted off with 1,514 cricket eggs, 233 swordtail fish, four oyster toadfish with electrodes in their heads, 18 pregnant mice, 135 snails, and 152 rats, of whom 96 were newborns and 24 had temperature and heart rate sensors attached to their skulls. |
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| The mice and cricket eggs aboard were backup contingents. Those originally loaded were replaced before lift-off when mechanical problems caused a 24-hour delay of the launch. The mission plan called for all of the mice embryos to develop and all of the cricket eggs to hatch during spaceflight, without ever experiencing gravity. | 
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The first casualty of the flight came, apparently, when a bat landed on
the Columbia’s external fuel tank late in the countdown. The bat
tried to escape when the booster rockets ignited, launch director Dave
King said, but was probably burned.
The 26-experiment Neuro-lab program began a day later with the abortion of nine mouse pregnancies, after which the anesthetized mothers were killed. The same day, space doctors David Williams and Jay Buckey Jr. killed and removed the brains of four rats. All 18 mice and 29 rats were killed and dissected before the flight was over, mostly to investigate the effects of gravity loss on brain development. |
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| In addition, 55 of the 96 baby rats died, 52 from maternal neglect. Three others were euthanized. The problem, flight veterinarian Richard Linnehan speculated, was that the baby rats couldn’t keep their positions at adult females’ nipples in order to nurse. Linnehan suggested changes in the design of the rat cages to keep the rats in more intimate proximity. | 
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Photograph of baby rat courtesy Oakland University |
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Linnehan, the medical doctors, and payload specialist Jim Pawelczyk
managed to save the remaining rats for killing and dissection as
scheduled after landing.
Linnehan refused an April 31 ground control order to kill an adult male rat who somehow managed to shake free of his electrode cap. After applying ointment to the wound, Linnehan told ground control, “He’s a happy, healthy, good-looking rat at this point.” |
Photograph of Dr. Richard Linnehan courtesy AVMA |
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| “My
guess is he may be attached to this guy. I don’t blame him,”
NASA chief veterinarian Joseph Bielitzki told Associated Press aerospace
writer Marcia Dunn.
The major animal research finding in flight was the observation that newborn rats, like all other mammals tested in space, tend to propel themselves by using their front limbs, making little use of their hind limbs. Seven Neurolab experiments were undertaken on the astronauts themselves, but were relatively painless, involving catching a spring-propelled ball and sitting in a rotating chair while a camera tracked their eye motion. They also tested the hormonal drug melatonin to see if it might remedy the sleeplessness usually afflicting space travelers. The most difficult experiment on the humans involved sticking a tiny needle into an obscure nerve behind the knee, taking from 10 to 40 minutes per astronaut to do. |
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