Possible Cause of Postpartum Depression Pinpointed

Treatment with THIP (Gaboxadol), a GABA receptor agonist originally intended to treat sleep disorders, ameliorated these effects in mice containing decreased levels of GABA receptors.

"Our thinking is that postpartum depression, and maybe premenstrual syndrome and premenstrual dysphoric disorder, may be due to impaired trafficking of these [GABA] receptors to the [neural] membrane," Mody said.

The next step, he said, is to determine whether human postpartum depression is caused by a similar defect.

"We don't know if this is the same mechanism in humans, but I think all indications are there," Mody said. "The women that are affected by the disorder, the hormone levels are not changed, they are not different than in unaffected women. So, we are confident that it must be the receptor trafficking mechanism that is affected, because the changes in hormone levels are pretty normal."

Dr. Julio Licinio, chairman of the department of psychiatry and behavioral sciences at the University of Miami Miller School of Medicine, praised the research as "very interesting," particularly its development of a new animal model of postpartum depression, which can aid both research and drug development.

"This is probably the strongest [animal] model I have seen in a long time," he said.

More information

For more on postpartum depression, visit womenshealth.gov.

SOURCES: Istvan Mody, Ph.D., Tony Coelho professor, neurology and physiology, department of neurology, David Geffen School of Medicine, UCLA; Jamie Maguire, Ph.D., assistant researcher, department of neurology, David Geffen School of Medicine, UCLA; Julio Licinio, M.D., professor and chairman, department of psychiatry and behavioral sciences, University of Miami Miller School of Medicine; Bernard Carroll, M.D., Ph.D., scientific director, Pacific Behavioral Research Foundation, Carmel, Calif.; July 31, 2008,Neuron