List of North American cities by population. This list of North American cities by population ranks cities based on the latest available official government census figures, estimates or projections for mid-year populations (unless otherwise noted) living within city limits. All cities with a population exceeding 500,000 are included. 1  1 List.  2 See also.
The pituitary gland sends signals to other glands, for example the thyroid gland, to produce hormones, such as thyroid hormone. The hormones produced by the pituitary gland and other glands have a significant impact on bodily functions, such as growth, reproduction, blood pressure, and metabolism.umors can cause damage to the pituitary gland or hypothalamus and can therefore result in a loss of function. Damage to the pituitary gland can also be caused by radiation, surgery, infections such as meningitis, or various other conditions. In some cases, the cause is unknown.
Deficiency of thyroid hormone may be due to lack of stimulation by the pituitary gland, defective hormone synthesis or impaired cellular conversion of T4 to T3 (often caused by mercury toxicity). The pituitary gland regulates thyroid activity through the secretion of thyroid-stimulating hormone (TSH).The combination of low thyroid hormone and elevated TSH blood levels usually indicates defective thyroid hormone synthesis, which is defined as primary hypothyroidism.he thyroid gland captures dietary iodine, synthesizes thyroid hormone from it, and stores thyroid hormone until it is needed. Colloid, the material in the center of the follicles, stores thyroid hormone in a large protein called thyroglobulin.