Reduced Serotonin Signaling
Disease Mechanism VII

Serotonin (also known as 5-HT) is a neurotransmitter used to communicate important information between nerve cells. Serotonin is sometimes referred to as the “feel good” neurotransmitter owing to its association with elevated mood levels. It also has many other functions in the central nervous system including roles in sleep, depression, memory, pain, and aggression. Recent studies on mice indicate that serotonin signaling is significantly reduced in mice models of HD compared to mice without HD. Having less serotonin and the products made from serotonin may greatly impact on the progression of HD. Because the connection between HD and serotonin signaling is a fairly new development, much more investigation needs to be done before there are clear answers. Decreased serotonin may be a contributor to the development of HD or it may simply be a result of another disease mechanism. Regardless of the cause for reduced serotonin, diminished signaling in the mouse model of HD may explain some of the common behavioral symptoms associated with HD in people. (For more information about the behavioral symptoms associated with HD, click here.)

Decreased serotonin is associated with several diseases, most notably depression. Consequently, a number of drugs are already available to help bring serotonin back to normal levels in the body. The main class of drugs for this purpose is called selective serotonin reuptake inhibitors (SSRIs). Recent research has shown that, in addition to alleviating symptoms associated with HD such as depression, SSRIs may also help delay the onset of HD and prevent the degeneration of nerve cells.

• About "HD and Serotonin"
• SSRIs
• Paroxetine
• Fluoxetine

Last Modified: 02/18/2006

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