Thyroid disease in women tests. The thyroid is a small gland in the front of the neck. The thyroid makes hormones called T3 and T4 that regulate how the body uses energy. Thyroid hormone levels are controlled by the pituitary gland, which is a pea-sized gland in the brain. It makes thyroid stimulating hormone (TSH), which triggers the thyroid to make thyroid hormone. In thyroid disease the immune system makes antibodies that damage thyroid cells and interfere with their ability to make thyroid hormone. Over time, thyroid damage can cause thyroid hormone levels to be too low. This is called an underactive thyroid or
Thyroid storm to sympathetic activation (see below). Sympathetic nervous system activation during times of stress may also play a significant role in thyroid storm. Sympathetic activation increases production of thyroid hormone by the thyroid gland. In the setting of elevated thyroid hormone, the density of thyroid hormone receptors (esp. beta-receptors) also increases, which enhances the response to catecholamines. This is likely responsible for several of the cardiovascular symptoms (increased cardiac output, heart rate, stroke volume) seen in thyroid storm. According to newer theories, thyroid storm results from allostatic failure in a situation where thyrotoxicosis hampers the development of non-thyroidal illness syndrome, which