Vet prof studies pain relief

by Jenny Bryers

Everyone has bumped, bashed or bruised some body part so that even the slightest pressure causes agony. In most cases, the injury heals and the body returns to normal, but in some cases, the pain remains long after the injury has otherwise healed.

Vjekoslav Miletic, a professor in the University of Wisconsin–Madison School of Veterinary Medicine Department of Comparative Biosciences, studies why this pain sometimes persists and what may be done to relieve it.

To pursue this study, Miletic has received $864,000 over four years from the National Institutes of Health. But he is especially honored by his two-year, $150,000 grant from the Christopher Reeve Paralysis Foundation.

“After we got this grant, it really put things in a different perspective for me,” he says. “It certainly provides more of an incentive to promote treatment of chronic pain.”

The Christopher Reeve Paralysis Foundation aims not only to support research on recovery from paralysis but also improve the lives of people suffering from chronic pain due to spinal cord injuries.

Miletic explains that chronic pain may be caused by a change in receptors, a change in chemicals used to bind receptors, or a rewiring of nerve fibers.

“There is almost a memory of pain that exists in the spinal cord after the injury,” Miletic says. “The nervous system is capable of generating different responses to the same stimulus.”

Miletic describes these variations as “plasticity.” He uses rats as a model to understand some of the chemicals involved – chemicals that trigger acute pain to change to chronic pain.

“In the hippocampus, plasticity allows you to learn and memorize,” Miletic says. “But in the spinal cord, this same plasticity is not good. Plasticity of spinal cord neurons causes hyperalgesia, a disorder in which pain is exaggerated, and allodynia, a condition in which stimuli cause pain that previously did not.”

Miletic is one of 38 researchers worldwide to receive a Christopher Reeve Paralysis Foundation grant in 2001.