The pituitary gland is divided into the posterior and anterior sections. The posterior pituitary releases the hormones oxytocin and ADH (Anti diuetic), however, it does not produce these hormones. The hormones are actually made in the hypothalamus and travel through a neuronal tract to the posterior pituitary gland, where it is released into the blood stream. Oxytocin stimulates mammery glands for milk secretion and stimulates the uterus for uterine contractions during child birth. ADH stimulates thirst and as a result less urine is produced to help rehydrate the body.
The Anterior Pituitary is composed of epithelial tissue and produces several different hormones. Growth hormone, prolactin and melanocyte-stimulating hormone work to stimulate a target organ directly. The others, Thyroid-stimulating hormone, ACTH, and Gonadotropin (FSH and LH) secrete hormones to effect other hormones which then stimulate a target organ or tissue. For example, Thyroid-stimulating hormone stimulates the Thyroid, triggering the release of Thyroxin, which regulates metabolic rate.
Many people in my family (including sibling and both parents) have hypothyroidism and so I decided to research this condition on-line. I learned that the disorder is a result of low levels of the hormones produced by the Thyroid gland, mostly, T3 and T4 and since most T4 is converted into T3 in the blood, this is the hormone of interest. The job of T3 is to regulate the metabolism of cells. The releases of thyroid hormones is regulated by a negative feedback system involving the hypothalamus, the pituitary gland and then the thyroid. The hypothalamus relases Thyrotropin releasing hormone which triggers the release of Thyroid-Stimulating hormone from the Pituitary Gland, which in turn sends a signal for the Thyroid gland to release its hormones. A disruption in any of these levels can result in a low production of Thyroid hormones.
The most common cause of this disorder is Hoshimoto's Thyroiditis Disease, an inherited disease, marked by an enlarged Thyroid gland that has difficulty producing its hormones. It is an autoimmune disease in which the body attacks the tissue of the gland. Other causes include a severe iodine difficiency or medications. Some medications used to treat hyperthyroidism actually have a dramatic effect by causing hypothyroidism. The treatment includes taking synthetic T-4 for the length of life of the patient. T4 is used instead of T3 because it effect is longer lasting and is converted into T3 easily.
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I myself suffer from TSH problems. It has been hard to maintain a constant balance with my levels. TSH stands for thyroid stimulating hormone. The tsh test is the main one that doctors use to diagnose hypothyroidism or hyperthyroidism, so it's and important test to understand. We have learned that this is produced in the anterior portion of the pituitary gland. Its function is to stimulate the thyroid to produce more thyroid hormone, so high levels of TSH usually indicates that your body isn't getting enough thyroid hormone, this is hypothyroidism. To low TSH means the opposite, hyperthyroidism. I know for me I kept taking my medication reguarly but yet my levels were never right. After about one year I was tired of my levels being so high that I would fall asleep all the time or they would change quickly and be really low. I started realizing that it wasn't when I was taking my levothroxine that changed it was my nexium. Nexium is for my GERD and it's an acid base inhibitor and that was changing my levels. So now I take my levothyroxine first thing in the morning and I have to sometimes bring my medication with me to take minimally 4 hours later. Now my levels are finally normal, I feel SO much better and my GERD is doing great. This taught me to be an advocate for yourself. The doctor was convinced that I was just not really taking my medication but I was and I knew I had to find something to prove I was right.
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