Sex Differences in Brain Neurotransmitter Involved in Depression

Medical researchers at the Montreal Neurological Institute (Canada) have reported that there is a significant difference in the rate of synthesis of serotonin in the brain of men and women. Serotonin is a neurotransmitter (chemical released between the brain cells to permit the transmission of impulses between them) associated with the cerebral basis of emotions. Severe depressed people have a lower level of serotonin than normals, as shown by PET scans of their brains. Although normal persons of both sexes have approximately the same level of serotonin, menís brains synthesize it 52 % faster than womenís. This difference may be the explanation for the finding that women are more than two times more prone to depression than men. The researchers also compared the response of brain serotonin to emotional stress in men and women. The impact of stress was four times larger in men than in women.

Proc Natl Acad Sci U S A 94(10), 5308-5313 (1997)