What are the symptoms of thyroid hormone resistance?
The most common symptoms are goiter and tachycardia. It has also been linked to some cases of attention deficit hyperactivity disorder (ADHD), although the majority of people with that diagnosis have no thyroid problems. An association with depression has been proposed.
What are the building blocks for thyroid hormone?
They are made in what are known as the follicular epithelial cells of the thyroid. Iodine is one of the main building blocks of both hormones. Our bodies can’t produce this trace element, so we need to get enough of it in our diet. Iodine is absorbed into our bloodstream from food in our bowel.
What is the target tissue of thyroid hormone?
| Endocrine gland/ source of hormone | Hormone | Target organ or tissue |
|---|---|---|
| Thyroid | Thyroxine (T4) Triiodothyronine (T3) | Most tissues |
| Calcitonin | Bone | |
| Parathyroids | PTH (parathyroid hormone) | Bone, kidneys, intestine |
| Thymus (regresses in adulthood) | Thymopoetin | T-lymphocyte cells in blood |
Does thyroid hormone regulate tissue growth?
In addition to its complex metabolic effects involved in the general mechanisms of body growth, thyroid hormone stimulates the production of growth factors, particularly EGF and NGF. Moreover, it affects GH and somatomedin production and also their tissue activity.
What causes thyroid hormone resistance?
Resistance to thyroid hormone is usually caused by a genetic mutation resulting in a defective beta receptor. Tissues in the body respond differently to high thyroid hormone levels depending on the relative amount of alpha versus beta receptor contained in that tissue.
What happens when thyroid hormone binds to its receptor?
Binding of thyroid hormone results in a conformational change in helix 12 of the TR transactivation domain, which displaces the corepressors from the receptor/DNA complex. Coactivator proteins are recruited, forming a DNA/TR/coactivator complex.
How do thyroid hormones affect target cells and tissues?
Thyroid hormones produce effects by docking with protein receptors in thyroid-sensitive tissues. The hormones can bind with receptors on the cell’s membrane surface and inside the cell on the mitochondria or in the nucleus.
How does thyroid hormone interact with its target tissue?
Control of T3 and T4 TRH causes the pituitary to release thyroid-stimulating hormone (TSH) which then travels to the thyroid gland via the bloodstream. TSH acts on the thyroid gland and causes the release of T3 and T4 into the blood, where the hormones are carried by proteins to their target tissues.
How do thyroid hormones affect target cells?
How does thyroid hormone regulate growth?
Thyroid hormones regulate growth by several mechanisms. In addition to their negative feedback effect on the stimulatory hormones thyrotropin-releasing hormone (TRH) and thyrotropin (TSH), thyroid hormones also regulate their receptors in various physiological and pathological conditions.
How is the thyroid hormone regulated?
The thyroid gland is regulated by thyrotropin releasing hormone (TRH) and thyroid stimulating hormone (TSH). In addition to TRH/TSH regulation by TH feedback, there is central modulation by nutritional signals, such as leptin, as well as peptides regulating appetite.
What are the symptoms of thyroid resistance?
The list of signs and symptoms mentioned in various sources for Resistance to thyroid stimulating hormone includes the 13 symptoms listed below: Goiter. Palpitations. Increased bowel movements. Menstrual abnormalities. Fatigue. Insomnia. Breathlessness.
What is the best medication for hypothyroidism?
Thyroid Hormone Replacement with Synthetic Hormone. Levothyroxine is the standard medication used for treating hypothyroidism. It is a synthetic thyroid hormone that when taken orally helps to stabilize the thyroid hormone levels in the body, thereby reversing the symptoms of poor thyroid activity.
What does thyroid hormone resistance syndrome mean?
Thyroid hormone resistance (also resistance to thyroid hormone (RTH), and sometimes Refetoff syndrome) describes a rare syndrome in which the thyroid hormone levels are elevated but the thyroid stimulating hormone (TSH) level is not suppressed, or not completely suppressed as would be expected. The first report of the condition appeared in 1967.
What is recombinant TSH for thyroid cancer?
Recombinant TSH (thyrotropin alfa) was approved by the U.S. Food and Drug Administration in 1998 for use as a tool in monitoring patients who have been treated for well-differentiated thyroid cancers. Recombinant TSH is a synthetic form of thyroid stimulating hormone, and it does just that- stimulates the thyroid tissue.
