Thyroid hormone has profound effects on cardiovascular function and metabolism, regulating heart rate, blood pressure, food intake, and metabolic rate.

Originally, thyroid hormone was thought to act directly on the target tissues; however, several recent studies have suggested that thyroid hormones effects are mediated by the central nervous system (CNS).

Researchers led by Jens Mittag at the Karolinska Institute in Stockholm, Sweden identified a population of neurons in the hypothalamus that are required for thyroid hormone regulation of blood pressure and heart rate. Loss of these neurons in mice resulted in elevated blood pressure and heart rate.

These findings demonstrate an important role for the hypothalamus in the regulation of cardiovascular function and indicate a connection between thyroid disease and cardiovascular disorders. In an accompanying commentary, Jürgen Wess of the National Institute of Diabetes and Digestive and Kidney Diseases discusses the link between developmental hypothyroidism and cardiovascular disease.

TITLE: Thyroid hormone is required for hypothalamic neurons regulating cardiovascular functions

Journal of Clinical Investigation