Growth hormone deficiency

Growth hormone deficiency is a condition that occurs when the pituitary gland fails to release enough growth hormone.

Growth hormone, also known as somatotropin, helps promote overall growth of the body, muscle mass development, protein synthesis, and carbohydrate and lipid metabolism.

So a deficiency in growth hormone, which can occur in kids and adults, results in problems in all of these areas.

Growth hormone is released by the pituitary which is a pea sized gland that is connected by a stalk to a part of the brain called the hypothalamus.

The hypothalamus secretes growth hormone releasing hormone which travels through a network of capillaries called the hypophyseal portal system.

Releasing hormone eventually reaches the anterior pituitary and triggers it to secrete growth hormone.

Growth hormone then travels via the blood to various target tissues in the body to stimulate growth. This is called the hypothalamic pituitary axis.

Normally, growth hormone is released in a pulsatile manner, throughout the day and peaks one hour after you fall asleep, but it is also secreted in response to various forms of internal and external stimuli.

For example, the hypothalamus senses when there’s hypoglycemia, or low blood sugar, and in response it secretes growth hormone releasing hormone.

Exercise causes the adrenal glands to secrete epinephrine and that stimulates the hypothalamus to react in the same way.

Estrogen and testosterone which are produced in high levels during puberty, stimulate the hypothalamus to release growth hormone releasing hormone as well.