The hypothalamus produces releasing hormones that target the anterior pituitary. In childhood, too little STH can cause pituitary dwarfism , while too much causes gigantism. Oversecretion in adulthood causes a thickening of skin and bones called acromegaly . B. Thyroid Gland 1. Its hormones, thyroxine and calcitonin influence metabolic rates, growth, and development and the body's calcium levels, respectively.
Hyperthyroidism increases heart rate and blood pressure and causes weight loss.
Goiter can result from a deficiency in iodine. C. Parathyroid Glands 1. These glands are embedded in the thyroid gland and respond to the changing levels of calcium in the blood. When calcium levels rise, the PTH levels are reduced. Calcitonin from the thyroid gland acts antagonistically to PTH and promotes deposition of calcium in bones.