U professor studied snails for new painkiller

Pain relief might as well have been the last thing associated with slimy, little snails gliding around in the garden, but not any more, thanks to J. Michael McIntosh, a doctor and professor of psychiatry at the U’s School of Medicine.

On Dec. 28, the U.S. Food and Drug Administration approved Prialt, a painkiller that gets its potency from cone snail venom. The unique discovery that the venom had sedative powers began when McIntosh entered the U in 1979 and began researching it.

The curious freshman started isolating and characterizing the painkiller in the venom of the Conus magus, a fish-hunting cone snail. He worked in the lab of U biologist Baldomero “Toto” Olivera who was using cone snails because they carry a variety of neurotoxins.

“Cone snails are creatures that produce tens of thousands of compounds on the nervous system and are selective,” McIntosh said. He discovered the component in the venom affected the nervous system, and then he purified it and determined its chemical structure.

After discovering the effects on the nervous system, U biologist Doju Yoshikami determined the component would block the sensors that transmit pain without blocking the motor, which could cause an individual to become paralyzed, according to McIntosh.

Olivera and Yoshikami developed omega-MVIIA for use in basic research in neuroscience. “It blocks communication between nerve cells, allowing researchers to learn what nerve circuits do normally by seeing what goes wrong when the connections are blocked,” Olivera said.

The university didn’t patent omega-MVIIA because the substance “didn’t have a definitive therapeutic use” at the time, he added.

“As with many basic science discoveries, the clinical importance of the discovery wasn’t appreciated at the time,” McIntosh said.

The Irish based company, Elan Corp., got FDA approval to sell Prialt for pain suffered by people with cancer, AIDS, injury, failed back surgery or certain nervous system disorders.

The drug, which is expected to be available this month or early February, is injected into fluid surrounding the spinal cord by external or implanted pumps about the size of a hockey puck, according to McIntosh.

McIntosh said his experience in the lab was “really an example of how research universities can provide unique experiences for undergraduate students by allowing them to participate in cutting-edge research.”

McIntosh currently focused on a study about receptors for nicotine and how it affects both memory and mood and how the toxins from the snails affect the neurotransmitters.

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