Adrenal Cortex: The Disclosure
The Adrenal Cortex
When I was a kid, I always have fun of watching movies that simple people tend to exhibit a phenomenon in which they themselves are able to carry objects that are four times heavier than them! This uncertain phenomenon is commonly called as the " adrenaline rush". This was made possible by the hormones that were produced via the adrenal gland.
Sections of the Adrenal Gland
The adrenal gland, also called as suprarenal glands because of its location above the kidneys, is a gland responsible for the production of hormones that contributes to the proper balance of the blood volume, as well as the pumping activity of the heart. Mainly it is subdivided to two regions which is the adrenal cortex, the outer portion and the adrenal medulla, the inner portion.
As to our case, our main focus is the outer portion of the adrenal gland, which is the adrenal cortex wherein the essential hormones are produced. According to morphology, the adrenal cortex is can also further subdivided into three zones and each individual section has its own specific hormone that it release or produce.
Three sections
1. Zona glomerulosa - this is the part wherein cell are intacted and these cells is the responsible for the production of mineralocorticoid.
2. Zona fasculita - the center portion in which glucocoticoids are produced
3. Zona reticularis - the section wherein the production for steroid hormones takes place, particularly for men.
Hormones
1. Mineralocorticoids
These hormones are the once that greatly influence the salt and water content of the blood inside our system. Aldosterone is the one which is the abundant of all these mineralocorticoid.
Now let's discussed the mechanism that govern this action in a manner that it is produced and its effect.
Mechanism of Aldosterone Production and its Function.
- In a condition wherein a person is suffering of dehydration or salt loss, a person will tend to decrease in blood volume and also simultaneous down of the blood pressure.
- This condition, triggers the juxtaglomerular cells in the kidneys to produce renin in the blood, which is an enzyme.
- Second, this enzyme as it travels in the blood will meet its partner which is the angiotensinogen and thereby produced the angiotensin I.
- Then, the angiotensin will travel in the blood and finds its mate which angiotensin-converting enzyme (ACE) specifically in the capillaries in the lungs, and converting it to angiotensin II.
- Accumalation of the angiotensin II in the blood, triggers the adrenal cortex to produce the aldosterone
- Aldosterone takes the responsibility of retention of more sodium ion and water in the kidneys.
- Thereby, less water and sodium ions are being excreted in the urine.
- Thus , blood volume now becomes to increase and the same as the blood pressure to its normal.
For better understanding of the concept, a link is given below:
" Pathway" by: captainsmitty121
"Aldosterone Role in the Kidney" by geneedic
2. Glucocorticoids
These hormones are contributors in metabolism and at the same time, reduces the stress.
Cortisol, corticosterone, and cortisone are three forms of glucocorticoids. Among these three, cortisol is considered to be the most abundant considering a percentage of 95% in the glucocorticoid activity.
Mechanism of Glucocorticoid Production
- In a condition wherein there is low level of glucocorticoids in the blood, the hypothalamus is stimulated to produce corticotropin releasing hormone
- Then, CRH compels the anterior pituitary gland to produce the adrenocorticotropic hormone.
- Finally, ACTH will go to the adrenal cortex promoting the production of the glucocorticoids.
Some Functions of Glucocorticoids
- Glucogenesis
- Gluconeogenesis
- Weakening of the immune response
- Anaerobic supply of energy
For better understanding of the functions of the glucocorticoids a link is given below:
"Glucocorticoid Mechanism of Action" by: geneedic
3. Androgens
Basically, androgens are steroid hormones that enhance masculine characteristics of a person. Androgens are secreted minimally form the adrenal cortex. A good example of this, is the bulking of the muscles especially for men.
References:
Books
Principles of Anatomy and Physiology 11th Edition by Tortora, Gerard and Derrickson, Bryan
Internet
June 15, 2010 at 3:30 AM
hi kevz. :D
your posts are informative and interesting. keep it up. i hope you can make them more interesting to read by relating factual stories. good work!