Introduction
Hormones are chemical messengers produced by endocrine glands that regulate various physiological activities in the body. Each hormone targets specific organs and tissues to perform essential functions. In this post, we will briefly discuss five important hormones: glucocorticoids, insulin, gastrin, androgens, and growth hormone.
(a) Glucocorticoids
- Endocrine Gland: Adrenal Cortex
- Target Organs: Liver, muscle, adipose tissue, immune cells
- Functions:
- Regulate metabolism of carbohydrates, proteins, and fats
- Suppress inflammation and immune responses
- Help the body respond to stress
- Increase blood glucose levels
(b) Insulin
- Endocrine Gland: Pancreas (β-cells of Islets of Langerhans)
- Target Organs: Liver, skeletal muscle, adipose tissue
- Functions:
- Promotes uptake of glucose by cells
- Lowers blood sugar levels
- Stimulates glycogen synthesis
- Inhibits gluconeogenesis and lipolysis
(c) Gastrin
- Endocrine Gland: G-cells in the stomach (pyloric antrum)
- Target Organs: Stomach (parietal cells)
- Functions:
- Stimulates secretion of hydrochloric acid (HCl)
- Promotes growth of gastric mucosa
- Enhances gastric motility
(d) Androgens
- Endocrine Gland: Testes (Leydig cells), also small amounts from adrenal cortex
- Target Organs: Male reproductive organs, muscles, bones, brain
- Functions:
- Promote development of male secondary sexual characteristics
- Stimulate sperm production
- Increase muscle and bone mass
- Influence male behavior and libido
(e) Growth Hormone (GH)
- Endocrine Gland: Anterior Pituitary (somatotrophs)
- Target Organs: Liver, bones, muscles, and adipose tissue
- Functions:
- Stimulates growth of bones and muscles
- Promotes protein synthesis
- Increases fat breakdown (lipolysis)
- Stimulates liver to produce insulin-like growth factors (IGFs)
Conclusion
These five hormones are crucial for maintaining homeostasis, regulating metabolism, growth, digestion, and reproductive functions. Understanding their source, target, and role helps in identifying various endocrine disorders and developing effective treatments.