Kilpnäärmerakkude

Kilpnäärmerakkude is the Estonian term for thyroid cells. These are specialized cells found in the thyroid gland, a butterfly-shaped endocrine gland located in the neck. Thyroid cells are primarily responsible for synthesizing and secreting thyroid hormones, namely thyroxine (T4) and triiodothyronine (T3). These hormones play a crucial role in regulating metabolism, growth, and development in the body.

There are several types of thyroid cells, each with distinct functions. Follicular cells are the most abundant type and form the structure of the thyroid gland, arranged in spherical sacs called follicles. Within these follicles, follicular cells produce thyroglobulin, a precursor protein that is then iodinated and conjugated to form T3 and T4. Parafollicular cells, also known as C cells, are located in the spaces between the follicles. These cells produce calcitonin, a hormone that helps regulate calcium levels in the blood, primarily by inhibiting bone resorption.

The activity of thyroid cells is regulated by the pituitary hormone thyroid-stimulating hormone (TSH), which is released from the anterior pituitary gland. TSH stimulates the production and release of thyroid hormones, creating a feedback loop that maintains stable hormone levels in the bloodstream. Malfunctions or abnormal proliferation of thyroid cells can lead to various thyroid disorders, such as hyperthyroidism (overactive thyroid) or hypothyroidism (underactive thyroid), and can also be implicated in the development of thyroid cancer.