Endocrinology is the name for the medical discipline that deals with hormones. The word “hormone” is derived from Latin word “Hormanein”, which means to stimulate or to activate.

The first definition of the hormone is “the substances secreted by endocrine glands into the bloodstream to affect distant tissues and organs with very small amounts.”

Hormones are secreted from special tissues called endocrine glands (also publicly known as internal secretory glands), but, we know that certain organs, which are not endocrine glands, secrete certain hormones.

Hormones can affect almost all bodily functions such as development, growth, reproduction, nutrition, hydration, metabolism, cardiovascular system, neurologic functions, sleeping, perspiration, etc.

Endocrinology is the medical discipline that is specialized in structures of endocrine glands, hypoactivity or hyperactivity, structures of one or multiple hormones secreted by these glands, secretion mechanisms and various factors managing the mechanisms as well as their effects on various organs, diseases caused by the said effects and their treatments.

Numerous hormones are secreted from endocrine glands in our body. Some of them are listed below:

Main hormones secreted by the pituitary gland: ACTH (Adrenocorticotropic Hormone), TSH (Thyroid Stimulating Hormone), LH (Luteinizing Hormone), FSH (Follicle Stimulating Hormone), PRL (Prolactin), ADH (Anti-diuretic Hormone),

Hormones secreted by thyroid gland: T4 (Thyroxin), T3 (Triiodothyronine),
PTH (Parathormone) from parathyroid gland,

Adrenal Glands: Adrenaline, Noradrenalin, Cortisol, Aldosterone, etc
Pancreas: Insulin, Glucagon

Ovaries: Ovary: Estrogen, Progesterone
Testicle: Testosterone

Hormones are secreted from various organs (for example: brain, cardiovascular system, gastrointestinal system, kidneys, etc.) other than those secreted by endocrine glands and they pose necessary effects on the whole body.