Prescription for trouble: antidepressants might rewire young brains.Prescribing antidepressants Antidepressants
Medications prescribed to relieve major depression. Classes of antidepressants include selective serotonin reuptake inhibitors (fluoxetine/Prozac, sertraline/Zoloft), tricyclics (amitriptyline/ Elavil), MAOIs (phenelzine/Nardil), and heterocyclics to children and pregnant women is becoming increasingly common. However, it hasn't been clear whether these medications pose a risk to the developing brain.
In a new study, researchers provide evidence that, in young mice, the antidepressants known as selective serotonin reuptake inhibitors Selective Serotonin Reuptake Inhibitors Definition
Selective serotonin reuptake inhibitors are medicines that relieve symptoms of depression.
Purpose (SSRIs) permanently alter the brain, resulting in a greater risk of depression and anxiety in adulthood.
SSRIs seem to combat depression by affecting a molecule, called a transporter, on the surface of some brain cells. The molecule's main role is to absorb serotonin, a brain chemical that regulates mood. SSRIs probably prevent the transporter from taking in serotonin, thereby increasing the amount of free serotonin in the brain and lightening a person's disposition.
Jay Gingrich and his colleagues at Columbia University Columbia University, mainly in New York City; founded 1754 as King's College by grant of King George II; first college in New York City, fifth oldest in the United States; one of the eight Ivy League institutions. had previously shown that mice engineered to be missing a gene for the serotonin transporter The serotonin transporter is a monoamine transporter protein. Function
It reuptakes serotonin in synaptic cleft and terminate its function. It allows neurons, platelets, and other cells to accumulate the chemical neurotransmitter serotonin, which affects emotions and show anxiety and depression once they reach adulthood. The mood problems of these knockout mice were unexpected, Gingrich says, because when SSRIs inactivate in·ac·ti·vate
1. To render nonfunctional.
2. To make quiescent.
in·acti·va the serotonin transporter in normal, mature mice, they ease depression symptoms, as they do in people.
"We thought that maybe the reason we're having this paradoxical effect is that in knockout mice, the [transporter] gene is disabled for the animal's life span, so it's rewiring the brain early in development to make the animals more susceptible to anxiety and depression later in life," he says.
To test this theory, Gingrich's team treated litters of both normal and knockout mice with fluoxetine fluoxetine /flu·ox·e·tine/ (floo-ok´se-ten) a selective serotonin reuptake inhibitor used as the hydrochloride salt in the treatment of depression, obsessive-compulsive disorder, bulimia nervosa, and premenstrual dysphoric disorder. , an SSRI SSRI selective serotonin reuptake inhibitor.
Selective serotonin reuptake inhibitor; a class of drugs that inhibit the reuptake of serotonin in the central nervous system, used to treat depression and other commonly known as Prozac. The time of treatment, from ages 4 days to 21 days, corresponds to the period from approximately the third trimester Noun 1. third trimester - time period extending from the 28th week of gestation until delivery
trimester - a period of three months; especially one of the three three-month periods into which human pregnancy is divided of pregnancy to age 8 years in people.
After the mice matured, the scientists exposed them to several stressful situations, such as mild foot shocks or new cages. Compared with normal mice that hadn't received the drug during their development, both knockouts and mice that had received fluoxetine earlier in life showed more signs of anxious and depressed behaviors. For example, these mice took significantly longer to try to avoid foot shocks and showed less interest in exploring new environments.
Gingrich and his colleagues presented the findings this week at the Neuroscience 2004 meeting in San Diego San Diego (săn dēā`gō), city (1990 pop. 1,110,549), seat of San Diego co., S Calif., on San Diego Bay; inc. 1850. San Diego includes the unincorporated communities of La Jolla and Spring Valley. Coronado is across the bay. and in the Oct. 29 Science.
According to Gingrich, the research suggests that the serotonin transporter plays a pivotal role in normal brain formation. Consequently, if SSRIs block the transporter's function while the brain is still developing, they could permanently disrupt mechanisms that control mood.
"Like all good studies, this raises more questions than it answers," says David Fassler, a clinical associate professor of psychiatry at the University of Vermont in Burlington. Although the results don't immediately translate to people, he says, "I think everyone agrees that we need more research on the long-term effects of these medications on children and adolescents and on children who may have been exposed prenatally."