Question on adrenocorticotropin (ACTH)

[princessd3]

I read today that ACTH controls the realease of aldosterone too. I always thought it was just tropic to the release of cortisol or corticosterone. Does that mean that when ACTH is released from the anterior pit (for instance under stressful situations), aldosterone is relased as well? How does that factor in if they're both controlled by ACTH?

---

Members don't see this ad.

 

[bgreet]

ACTH stimulates the production of corticoid hormones by the adrenal cortex. One such corticoid produced (a mineral corticoid) by the adrenal cortex is Aldosterone. So basically what happens is ACTH is secreted by the anterior pituitary gland, which stimulates production of corticoids by the adrenal cortex. The two main corticoids released by the adrenal cortex are Aldosterone and Cortisol. Hope this helped.

 

[DieselPetrolGrl]

?The two main corticoids released by the adrenal cortex are Aldosterone and Cortisol.?

Ok I know cortisol is high during stress and it works to max blood sugar, right?
But what about aldosterone ? any conection to rennin? Is renin made by the kidney ? to cause erythrocyte formation? And is aldosteone a diuretic or a vaso-pressin ?like hormone?

(PS: I am so sorry if my post is ridden with fallacies..... I am very hazy on this and cant understand this at all ? please help by correcting my wrongful assumptions ~ THANKS ~)

 

[princessd3]

ACTH stimulates the production of corticoid hormones by the adrenal cortex. One such corticoid produced (a mineral corticoid) by the adrenal cortex is Aldosterone. So basically what happens is ACTH is secreted by the anterior pituitary gland, which stimulates production of corticoids by the adrenal cortex. The two main corticoids released by the adrenal cortex are Aldosterone and Cortisol. Hope this helped.

Yeah that much I know. What I really want to know is. Since ACTH stimulates both (at the same time?) when the body is under stress and needs energy and cortisol does whatever it does. Why would aldosterone be released at the same time. Or maybe they're not both secreted at the same time. In other words, where is the connection what does one (cortisol) have to do with the other (aldosterone). It seems like under two different conditions they're released. Correct? Or are they released at the same time? If they are how is the effect of one related to the effect of the other. Get my question?

 

[Groove]

Yes, cortisol increases blood sugar. Renin is released in response to low blood pressure. Aldosterone causes increased Na and Cl reabsorption in the kidneys and increases K and H secretion. It causes a net increase in solute particles in the blood which has an effect of increasing blood pressure. Aldosterone basically helps regulate electrolyte balance.

 

[princessd3]

?The two main corticoids released by the adrenal cortex are Aldosterone and Cortisol.?

Ok I know cortisol is high during stress and it works to max blood sugar, right?
But what about aldosterone ? any conection to rennin? Is renin made by the kidney ? to cause erythrocyte formation? And is aldosteone a diuretic or a vaso-pressin ?like hormone?

(PS: I am so sorry if my post is ridden with fallacies..... I am very hazy on this and cant understand this at all ? please help by correcting my wrongful assumptions ~ THANKS ~)

When the juxtaglomerulosa cells (composed of cells of the afferent artery and distal convoluted tubules of the kidney) sense a drop in blood pressure or a decrease in filtrate they release renin which converts angiotensinogen (from the liver) to Angiotensi I. ACE converts Angiotensin I (in the lungs) to Angiotensin II. This is a vasoconstrictor. Raises blood pressure. Another way to raise blood pressure is to increase blood volume. So Angiotensin II stimulates the release of Aldosterone from adrenal cortex. Aldosterone acts on the distal convoluted tubules to increase the number of Na/K AtPases there. More Na is reabsorped into the blood. High osmolarity of the blood causes the posterior pituitary to release Vasopressin which creates porins in the collecting ducts. This way more water is reabsorbed increase blood volume and increasing blood pressure.
Make sense?

 

[bgreet]

Princessd3: Overall ACTH is released in times of stress. It does work to have the adrenal cortex secrete both aldosterone and cortisol at the same time. Unfortunately, the benefit of cortisol under stressful situations really isnt fully understood, but its though to perhaps have anti-inflammatory properties (as well as diminishing the capacity of the immune system). For this reason it's hard to depict the exact relationship both aldosterone and cortisol have in connection with each other.

 

[Fusion]

Not to complicate matters or anything, but some androgens are released by the adrenal cortex as well. The adrenal cortex is composed of the zona glomerulosa (outer layer), zona fasciculata (middle layer), and zona reticularis (inner). ACTH acts on the entire cortex to release the hormones aldosterone, cortisol, and androgens, respectively. I took medical endocrinology in grad school, but I do not recall exactly why or when cortisol and androgens are released along with aldo in response to ACTH. But I think the androgen thing would be good to know in case it pops up in an MCAT passage. The androgens released by the adrenal cortex are the major source of androgens in females, but not so much in males.

A major effect of cortisol is to raise blood sugar. Cortisol and epinephrine are "stress" hormones. What does your body want in times of stress? Glucose=energy! Glucagon and growth hormone also raise blood sugar, but not so much in response to stress.

Hope this helps.

 

[willthatsall]

Yeah, the androgens from the adrenal gland make a much bigger difference in women than in men since it is a very small amount compared to the testes. And don't worry about memorizing the layers, either.