Thyroid Hormones May Influence Neural Function, Study Suggests

February 11, 1997

ATHENS, Ohio -- Changes in hormones produced by the thyroid gland may influence how certain neurons in the central nervous system function, a new study at Ohio University suggests. The findings could have implications for researchers studying how thyroid hormones affect different bodily functions.

The study also could be important to physicians who prescribe thyroid hormones -- known for their mood-altering capability -- to treat depression, said Bill Henley, associate professor of biological sciences at Ohio University and co-author of the study.

The research was published in the February issue of the American Journal of Physiology.

Scientists examining the brains of rats with underactive thyroid glands -- or hypothyroidism -- found differences in neuronal responses to serotonin, a neurotransmitter that is important for circulatory control. Rats in the study received central administration of a drug that mimics serotonin and normally causes an increase in blood pressure.

"In the normal rat, blood pressure rose markedly, but in hypothyroid rats, blood pressure responses were attenuated substantially," Henley said. "This study, coupled with previously reported findings, tells us that the serotonergic neurons in the hypothyroid brain are different, and that has very important physiological implications."

Learning about these implications could increase physicians' understanding of the impact thyroid disease, which affects about 200 million people in the world, has on various bodily functions, Henley said.

"It's been known for years that thyroid hormones have a profound impact on developing brains, but most people believe that they're not important in the mature central nervous systems," he said. "But our findings provide evidence of an important impact on the brains of mature rats."

Understanding how mature brains react to these hormones is important for psychiatrists who prescribe these drugs to treat depression.

"This could change the way physicians use thyroid hormones as an adjunct therapy in the treatment of depression," Henley said.

The next phase of Henley's study will be to determine if other neural functions are affected by thyroid hormones.

"It's probable that the impact we're seeing on the serotonergic neurons is not specific to those neurons," he said. "Hypothyroidism is likely to cause broad-based disturbances in a host of neural functions."

Contact: Bill Henley, 614-593-2270; Written by Kelli Whitlock, 614-593-0383;

Ohio University

Related Depression Articles from Brightsurf:

Children with social anxiety, maternal history of depression more likely to develop depression
Although researchers have known for decades that depression runs in families, new research from Binghamton University, State University of New York, suggests that children suffering from social anxiety may be at particular risk for depression in the future.

Depression and use of marijuana among US adults
This study examined the association of depression with cannabis use among US adults and the trends for this association from 2005 to 2016.

Maternal depression increases odds of depression in offspring, study shows
Depression in mothers during and after pregnancy increased the odds of depression in offspring during adolescence and adulthood by 70%.

Targeting depression: Researchers ID symptom-specific targets for treatment of depression
For the first time, physician-scientists at Beth Israel Deaconess Medical Center have identified two clusters of depressive symptoms that responded to two distinct neuroanatomical treatment targets in patients who underwent transcranial magnetic brain stimulation (TMS) for treatment of depression.

A biological mechanism for depression
Researchers report that in depressed individuals there are increased amounts of an unmodified structural protein, called tubulin, in lipid rafts compared with non-depressed individuals.

Depression in adults who are overweight or obese
In an analysis of primary care records of 519,513 UK adults who were overweight or obese between 2000-2016 and followed up until 2019, the incidence of new cases of depression was 92 per 10,000 people per year.

Why stress doesn't always cause depression
Rats susceptible to anhedonia, a core symptom of depression, possess more serotonin neurons after being exposed to chronic stress, but the effect can be reversed through amygdala activation, according to new research in JNeurosci.

Which comes first: Smartphone dependency or depression?
New research suggests a person's reliance on his or her smartphone predicts greater loneliness and depressive symptoms, as opposed to the other way around.

Depression breakthrough
Major depressive disorder -- referred to colloquially as the 'black dog' -- has been identified as a genetic cause for 20 distinct diseases, providing vital information to help detect and manage high rates of physical illnesses in people diagnosed with depression.

CPAP provides relief from depression
Researchers have found that continuous positive airway pressure (CPAP) treatment of obstructive sleep apnea (OSA) can improve depression symptoms in patients suffering from cardiovascular diseases.

Read More: Depression News and Depression Current Events is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to