
Growth hormone is manufactured by the pituitary gland of the brain. The pituitary gland is one of many found in the endocrine system. Three such glands are found in the brain: the pineal, the pituitary, and the hypothalamus. Growth hormone secretions are peptide hormones that belong to the group of short polypeptide chains and small proteins.
It contains approximately 191 amino acids, considered a chemical signaling mechanism that sends signals (instructions) to cells found in extracellular fluids for the regulation of a number of metabolic functions. Click here to buy HGH online now.
Table of Contents
About Growth Hormone Secretion Time
Growth hormone is manufactured in the pituitary gland and has a number of functions in the human body:
- Is important in the activation or de-activation of enzymes
- Stimulates cellular division and replication (mitosis)
- Causes changes in the permeability/potential of cellular membranes
- Stimulates protein synthesis
- Acts as a regulator of a number of molecules, cellular structures, and tissues and organs in the body
Growth hormone secretion provides either direct or indirect responses or actions in the body. Direct actions of it involve metabolic and anti-insulin functions such as the metabolism of fats and carbohydrates.
Carbohydrate metabolism is affected by growth hormone secretion by increasing levels of blood glucose and promoting a number of additional anti-insulin effects. When it comes to fat metabolism, growth hormone can increase the breakdown of fat in the body.
Growth hormone however, is most known for its indirect actions, or growth-promoting actions. Growth hormone stimulates the production of insulin-like growth factors in the liver. These factors affect skeletal tissues such as formation and growth of bone and cartilage, as well as extraskeletal functions involving synthesis of proteins, cellular growth, replication, and proliferation.
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What Stimulates Growth Hormone Secretion?
While the pituitary gland is responsible for manufacturing growth hormone and other hormones, and is also responsible for overseeing the maintenance, function, and secretion of other hormone glands in the body, it receives many of its instructions from the hypothalamus, also located in the brain.
The hypothalamus is a regulator of numerous body functions, especially those of the autonomic system. For example, the hypothalamus and the hypothalamus region is responsible for body temperature, breath rate, heart rate, fluid levels and other aspects of our bodies that we have no control over.
When the hypothalamus senses the levels of growth hormone are low, it sends a chemical messenger in the form of a hypothalamic neurohormone called growth hormone-releasing hormone (GHRH) to stimulate secretions of growth hormone into the bloodstream.
If levels are adequate the hypothalamus secretes somatostatin to instruct the pituitary gland to maintain levels where they are or to decrease production and secretion of growth hormone. Find out more here.
Hormone Secretions In the Body
This same process is repeated when it comes to other hormone secretions in the body. While growth hormone’s basic function is to stimulate bone growth and the growth of other tissues, it does promote a number of additional physiological responses.
Growth hormone is typically stimulated by low levels of growth hormone as well as other triggers that can include an increased level of amino acids in the blood, hypoglycemia or low blood sugar, decreased levels of fatty acids, lack of exercise, or other body stressors. Typically growth hormone secretion increases during exercise and decreases during sleep.
Growth hormone secretions can be inhibited by a number of medical conditions including hyperglycemia (high blood sugar) hyperlipidemia (increased cholesterol), obesity, and a number of emotional and mental disorders such as stress, depression, and so forth.
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Maintenance of the secretion processes in the body require careful balances. Too much or too little of any hormone, including growth hormone, can cause a ripple effect on other hormones, their functions, and physiological, psychological, and emotional processes.
Growth Hormone Secretion Regulation
Too much or too little growth hormone secretion can lead to pituitary dwarfism or gigantism in children, depending on levels, or a coefndition known as acromegaly in adults.
Acromegaly occurs when bones and other connective tissues in the hands, feet, and facial structures grow at an accelerated and abnormal proliferation rate, leading to deformities.
This condition is often considered a potential risk to bodybuilders or athletes who inject high dosages of growth hormone into the body or engage in such practices for long periods of time. Risks also increase when pituitary and hypothalamus glands are already functioning properly.
Levels of growth hormone generally begin to decline in adulthood (around the mid-30s). In most cases, decline of growth hormone secretion caused by normal aging processes is not treated with growth hormone replacement therapy, although a doctor may recommend altering lifestyle and diet to promote foods rich in amino acids, which make up a great part of the molecular composition of growth hormone.
To ensure that growth hormone levels are adequate based on age, schedule a visit with a physician and, under his or her guidance, a blood test may determine whether your growth hormone secretion levels are within adequate range based on age and health.
References
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