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Understanding Endocrinology
The neural system and the endocrine system jointly coordinate and regulate the physiological functions in the body.
Neural coordination is fast, very exact, and short-lived, whereas chemical coordination is usually slow, widespread, and long-lasting.
All cells of our body are not innervated by nerve fibers but the cellular function needs to be continuously regulated so a special kind of coordination and integration has to be provided. This function is carried out by the endocrine system.
The branch of biology which deals with the study of the endocrine system and its physiology is known as “Endocrinology“.
Thomas Addison is known as the father of Endocrinology, he was an English physician and scientist.
Types of gands
(i) Endocrine glands: These are ductless glands and pour their secretion directly into the blood. Their secretions are called hormones.
Examples: Hypothalamus, Pituitary, Pineal, Thyroid, Parathyroid, Thymus, Adrenal, Pancreas, and Gonads
(ii) Exocrine glands: These are ducted glands that secrete the digestive enzyme, milk, sweat, etc.
Examples: Mammary gland, or breast, sweat gland, salivary gland, stomach, pancreas, duodenum, …
(ii) Heterocrine / mixed glands: They have both exocrine and endocrine tissues.
Examples: Pancreas, testes, and ovaries, …
Types of endocrine glands
Organized endocrine gland: Glands where hormone-producing cells present in cluster/tissue form called organized endocrine gland.
Examples: Hypothalamus, Pituitary, Pineal, Thyroid, Parathyroid, Thymus, Adrenal, Pancreas, and Gonads.
Non-organized endocrine gland: Glands where hormone-producing cells are present in the scattered form called non-organized or diffused endocrine tissue.
Example: Heart (β – Trophin, Hepcidin), Liver (Hepcidin), Kidney (Insulin-like growth factors, Angiotensinogen, Thrombopoietin), Gastrointestinal tract (CCK, Secretin, Gastrin) …etc.