SSRI antidepressants actions studied

MEDFORD, Mass., Dec 19, 2005 -- Johns Hopkins scientists say the beneficial effects of a popular class of antidepressants may be the result of increased nerve-fiber growth in the brain.

The study was led by Dr. Vassilis E. Koliatsos, a neuropathologist at the Johns Hopkins University School of Medicine.

The researchers found selective serotonin reuptake inhibitors increase the density of nerve-impulse-carrying axons in the frontal and parietal lobes of the neocortex and part of the limbic brain that control the sense of smell, emotions, and motivation.

"It appears SSRI antidepressants rewire areas of the brain that are important for thinking and feeling, as well as operating the autonomic nervous system," said Koliatsos.

Axons conduct chemically driven nerve impulses away from the cell body toward a narrow gap known as a synapse. Among the chemicals involved are such monoamines as norepinephrine and serotonin.

Antidepressants, such as Prozac, Zoloft and Paxil, have been thought to increase synaptic concentrations of serotonin and norepinephrine, enhancing or stimulating their transference.

"But our findings ... may offer a better explanation of why antidepressants are effective and why they take time to work," Koliatsos said.

The study appears in the January 2006 issue of the Journal of Neurochemistry.
 

Latest posts

Top