Introduction to Endocrinology

Photo credit: voicesofglass.com

Just like me, you may have wondered at least once in your life why we have mood swings, how and why our bodies develop, how we produce energy, and how the different reactions in our bodies occur. Well, here's the answer to your questions.

 Endocrinology is the branch of medicine that deals with the endocrine glands and their secretions. The endocrine system is the system of glands which help control bodily metabolic activity. The term “endocrine” refers to the internal secretion of biologically active substances whereas the term “exocrine” refers to the secretion outside the body.

Photo credit: Encognitive (encognitive.com)

Endocrine Function

The nervous and the endocrine system are the ones responsible for the transmission of information throughout the body. They are called the physiologic regulatory systems. The nervous system transmits information by carrying messages between the peripheral tissue and brain through a network of nerve cells while the endocrine system conveys information by the use of hormones. Hormones are chemical messengers released by the endocrine glands into the bloodstream and to another tissue where they can act to elicit their specific action to the target tissue.

The most important endocrine glands are the anterior pituitary and the hypothalamus because they are the primary regulators of the endocrine system. The hypothalamus is responsible for secreting neuropeptide hormones (releasing hormones) into the portal circulation of the pituitary gland whenever there is an external or internal stimuli. Releasing hormones stimulate the release of anterior pituitary hormones which then give effect to other endocrine glands.

Here's a short video to know more about the hormones released by the pituitary gland:

Functions of Hormones

Hormones play an important role in the human body. They preserve homeostasis, regulate metabolism, control growth and development, and influence one’s behavior. The following are the functions of hormones:

• To maintain homeostasis or stable internal environment in the body fluids.
• To regulate the growth and development of one’s body.
• To facilitate sexual maturation, preserve sexual rhythms, and help in reproductive process.
• To control the production of energy and metabolic rate.
• To facilitate the body in adjusting during stressful and emergency situations.
• To inhibit or promote the release of other hormones in the body.

The specific functions of each organ/gland and the hormones that they produce will be discussed in my next blog entry.

References:

Greenspan, F., Baxter, J., Basic and Clinical Endocrinology, 4th Edition

Kaplan, L., Pesce, A., Clinical Chemistry Theory, Analysis and Correlation
Kaplan, A., Toivola, B., Ophain, K., Lyon, A., Jack, R., Clinical Chemistry: Interpretation and Techniques, 4th Edition