ADH vs Aldosterone: Difference and Comparison

“The human body is the most complex system ever created. The more we learn about it, the more we appreciate what a rich system it is.” This quote is by Bill Gates, and how truthful it is.

The human body is a very complex structure with various body parts, organs, cells, hormones, and many other elements that each have particular tasks to complete and are in use when in need.

Two of these are ADH and Aldosterone hormones.

Key Takeaways

1. “ADH” (Antidiuretic hormone) is a hormone produced by the hypothalamus and secreted by the pituitary gland that regulates the body’s water balance by increasing the reabsorption of water in the kidneys. At the same time, “Aldosterone” is a hormone produced by the adrenal glands that regulates the balance of sodium and potassium in the body by increasing sodium reabsorption and potassium excretion in the kidneys.
2. ADH is released in response to dehydration or low blood volume, while aldosterone is released in response to low blood pressure or sodium levels.
3. ADH and aldosterone work together to maintain the body’s balance of fluids and electrolytes, and their dysfunction can lead to various health problems, such as dehydration, electrolyte imbalances, and hypertension.

ADH vs Aldosterone 

ADH (antidiuretic hormone) regulates water balance in the body by promoting water reabsorption in the kidneys. Aldosterone regulates electrolyte balance by promoting salt reabsorption in the kidneys. Aldosterone also additionally helps in the execration of potassium from the body.

ADH, or more certainly, Antidiuretic hormone, is a water-conserving hormone, in simple terms. It helps the body to reabsorb water by stimulating water channels into the membranes of kidney tubules (A tube in the kidney that contains cells that clean the blood by filtering them.)

ADH and Aldosterone belong to different hormones of the body: It is a peptide hormone; they are those hormones whose molecules are of proteins or peptides. They can pass through the cell membrane.

The adrenal glands release Aldosterone, a corticosteroid hormone class of steroid hormones.

The primary function of Aldosterone is stimulating sodium by absorbing Sodium(Na) through the kidneys, thus regulating water and salt balances in the body.

Comparison Table

Parameters of Comparison	ADH	Aldosterone
Another name	Antidiuretic hormone/ Vasopressin	Mineralocorticoid
Main use	Control blood pressure and volume, help in retaining water in the body.	Absorption of sodium to regulate water and salt in the body.
Medication Side effects	Dizziness, chest pain, vomiting, fever	Low heart rate, fatigue, and muscle weakness
Hormone type	Peptide hormone	Steroid hormone
Secreted from	Posterior pituitary gland	Adrenal glands

What is ADH?

The name “Vasopressin” translates Vaso for “related to blood vessels” and “pressin”, meaning to “squeeze something.” The main job of ADH is to keep water and food in the human body.

It synthesizes in Hypothalamus and secrets from the posterior pituitary gland. No, it doesn’t hold ADH but acts as a storage house. It is mainly used once the blood pressure decreases or increases.

If the fluid volume is high, it will go down. i.e., if the amount of salt is more in the body than water, the body will have low blood pressure, and that’s where the work of ADH starts.

It helps in the following functions:

1. If a body suffers from hypovolemia (not enough blood volume), ADH helps increase the blood volume.
2. It also helps increase the volume of blood pressure by allowing the body to reabsorb water at the kidneys, which will increase the blood volume, increasing the blood pressure.
3. When the blood is concentrated with excessive sodium, it should be diluted as it is unhealthy to have this mineral in high form in the body. ADH is released, and reabsorbing reduces the sodium level to normal again.

It has a very short half-life, between 16–24 minutes.

What is Aldosterone?

Aldosterone is a steroid hormone that travels through the plasma membranes of target cells.

Aldosterone’s primary function is that it causes kidneys to get ahold of water and sodium and get rid of the potassium excreted into the urine. It is released when the blood pressure of the body gets low.

Following is the process of Aldosterone getting produced:

1. The nephron in the kidneys secrets renin, which then travels into the liver.
2. The Traveled renin makes its way to angiotensin I.
3. Angiotensin I travels to the lungs, converting it into angiotensin II.
4. Angiotensin II, then lastly, goes to the adrenal glands that are above the kidneys to produce Aldosterone.

The main things or body functions that the Aldosterone hormone help in are: Helping retain water in the kidney, increasing sodium in the body, Decreasing the potassium level, and raising blood pressure when it is low.

The plasma half-life of Aldosterone is not more than 20 minutes.

Main Differences Between ADH and Aldosterone 

1. ADH is a Peptide hormone, while Aldosterone is a steroid hormone.
2. Aldosterone drags water through increased tonicity, while ADH uses water channels.
3. Osmolarity (the number of osmoles of a solute in a litre of solvent) isn’t affected by Aldosterone, but in ADH, Osmolarity changes without actually affecting osmoles.
4. The membrane that separates the layers of cells is water-permeable in Aldosterone, while in ADH, the cells are not water-permeable.
5. The secretion of ADH hormone is from the posterior pituitary gland, as opposed to, Aldosterone, which is synthesized and secreted by the adrenal cortex.
6. The Aldosterone hormone synthesis is in the same place that secretes it: the adrenal cortex, while ADH, on the other hand, is synthesized in the hypothalamus.

References

1. https://www.jci.org/articles/view/105900
2. https://journals.physiology.org/doi/full/10.1152/advan.00051.2001?HITS=10&hits=10&FIRSTINDEX=0&searchid=1018374170515_241&stored_search=&journalcode=ajpadvan&RESULTFORMAT=&titleabstract=aldosterone&maxtoshow=