Endocrinology: Introduction

Endocrinology is an area of medicine which deals with endocrine glands along with their function. An endocrine gland is a collection of cells which generates and secretes chemical messengers. These chemical messengers, often known as hormones, convey information and directions from one cell to another. Each hormone specifically influences cells that are programmed to accept and to react to its message. 

The major function of the endocrine system is homeostasis. It maintains an environment that is stable for the body. Also, this system promotes different structural changes for the body’s development.

Hormone’s physiologic functions are divided in three areas: a) maintenance of homeostasis, b) growth, and c) reproduction.

Maintenance of homeostasis

     All hormones can affect homeostasis, the most important are the following:

• TH – controls 25% of the basal metabolism in most of the body tissues.
• PTH – it regulates phosphorus and calcium levels of the body.
• Insulin -  maintains normal glucose content in the body.
• Cortisol – use permissive action for most hormones.
• Vasopressin – it controls renal free-water clearance.
• Mineralocorticoids – it manages vascular volume and electrolyte concentration in serum.

Growth

     Since multiple hormones mediate the phenomenon of growth, understanding hormonal interactions is essential in the diagnosis and management of different growth disorders.

Reproduction

     The stages of reproduction involve an interchange of multiple hormones. These include the following:

• Sex determination during fetal period
• Sexual maturation (puberty)
• Pregnancy
• Reproductive capability at menopause

This is an illustration of the different glands involve in the endocrine system.


Image credit : http://kidshealth.org/parent/general/body_basics/endocrine.html#

The Major Human Endocrine glands and Functions

Endocrine gland	Function
Pituitary gland	It is also called as the “master gland”. Together with the hypothalamus, it produces hormones which are significant to female menstrual sequence, pregnancy, birth and lactation. The hypothalamus regulates the production of hormones.
Thyroid gland	It produces hormones which regulates body metabolism. Its hormones are important in body growth and brain development.
Pancreas	It produces digestive enzymes into the body’s small intestine. It regulates the level of the body's blood sugar.
Adrenal glands	They produce hormones in response to stress (anger, fright etc.). It secretes anti-inflammatory hormones.
Sex organs	It facilitates the secretion of sex hormones.
Pineal gland	It secretes hormones that encourage sleep. It depresses that activity of the sex organs.

To furthermore understand the mechanism of the endocrine system, please watch this video.

Video Credit: http://www.youtube.com/watch?v=xKkKOBd0fT0&feature=related

The Endocrine System can be divided into three type of conditions:

Hormone Deficiency 

Most hormone deficiency states can be attributed to destruction of glands caused by infection, inflammation, surgery or autoimmunity. Mutations is a number of hormones, their receptors, enzymes and channels can also lead to deficiencies.

Hormone Excess 

Conditions like hormone excess can be caused by autoimmune disorders, neoplastic growth of edocrine cellsor excess hormone supervision.

Hormone Resistance

Hormone resistance conditions are caused by inherited defects in the membrance receptors, in the nuclear receptors, or in the pathways that transduces receptor indicators.

“Any fool can know. The point is to understand.” 

― Albert Einstein

Thank you for reading my post! Please look forward to my next topic.

References:


J. Jameson; Harrison's Endocrinology, 2nd edition; 2010

http://kidshealth.org/parent/general/body_basics/endocrine.html#

http://biology.clc.uc.edu/courses/bio105/endocrin.ht

http://www.buzzle.com/articles/endocrine-system-function.html

http://www.beedictionary.com/meaning/endocrinology