Growth hormone

Definition

Growth hormone, also known as somatotropin, is a peptide hormone produced by the anterior pituitary gland that stimulates growth, cell reproduction, and cell regeneration in humans and other animals. This hormone plays a crucial role in regulating metabolism and promoting the growth of tissues, making it essential for overall health and development throughout life.

5 Must Know Facts For Your Next Test

1. Growth hormone release is regulated by the hypothalamus, which secretes growth hormone-releasing hormone (GHRH) and somatostatin to control its levels.
2. In children, growth hormone is crucial for normal physical growth, while in adults, it helps maintain muscle mass and supports metabolic functions.
3. Deficiency in growth hormone can lead to growth disorders in children and metabolic issues in adults, while excess can cause acromegaly, leading to abnormal growth of bones and tissues.
4. Growth hormone also influences lipid metabolism by promoting lipolysis, which helps to reduce fat stores while increasing protein synthesis.
5. The secretion of growth hormone follows a diurnal rhythm, with peak levels occurring during deep sleep and exercise, reflecting its role in recovery and metabolic regulation.

Review Questions

• How does growth hormone integrate with metabolic processes in the body?
  • Growth hormone plays a vital role in integrating metabolic processes by stimulating the production of IGF-1, which promotes cell growth and regeneration. It also enhances protein synthesis while encouraging the breakdown of fats for energy. This dual action of promoting anabolism while increasing energy availability illustrates how growth hormone is key in managing both growth and metabolism.
• What are the physiological consequences of both growth hormone deficiency and excess?
  • Growth hormone deficiency can lead to significant health issues such as stunted growth in children and increased body fat along with reduced muscle mass in adults. Conversely, an excess of growth hormone can lead to conditions like acromegaly in adults, characterized by enlarged bones and tissues. These conditions highlight the importance of maintaining balanced levels of growth hormone for overall health.
• Evaluate the implications of altered growth hormone levels on amino acid metabolism and overall protein synthesis.
  • Altered levels of growth hormone significantly impact amino acid metabolism and protein synthesis. A deficiency can result in decreased protein synthesis, leading to muscle wasting and impaired recovery from injury. Conversely, excessive growth hormone enhances amino acid uptake into cells, promoting greater protein synthesis which can benefit muscle mass but may also lead to adverse effects if unregulated. Understanding these dynamics is crucial for managing metabolic disorders linked to growth hormone levels.

Related terms

Insulin-like growth factor 1 (IGF-1): A hormone produced in response to growth hormone that mediates many of its growth-promoting effects on tissues, especially bone and muscle.

Pituitary gland: A small gland located at the base of the brain responsible for producing various hormones, including growth hormone, which regulate several bodily functions.

Metabolism:

The set of life-sustaining chemical reactions in organisms that convert food into energy, involving both catabolic and anabolic processes influenced by various hormones.