Gesundheit und Prävention

siehe Ton English: The thyroid gland is a butterfly-shaped organ and is composed of two cone-like lobes or wings: lobus dexter (right lobe) and lobus sinister (left lobe), connected with the isthmus. The organ is situated on the anterior side of the neck, lying against and around the larynx and trachea, reaching posteriorly the oesophagus and carotid sheath. The thyroid gland is covered by a fibrous sheath, the capsula glandulae thyroidea, composed of an internal and external layer. Between the two layers of the capsule and on the posterior side of the lobes there are on each side two parathyroid glands. The production of thyroxine and triiodothyronine is regulated by thyroid-stimulating hormone (TSH), released by the hypothalamus. The thyroid and thyrotropes form a negative feedback loop: TSH production is suppressed when the T4 levels are high, and vice versa. In areas of the world where iodine is lacking in the diet, the thyroid gland can be considerably enlarged, resulting in the swollen necks of endemic goitre.