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By the end of this section, you will be able to:
  • Describe how each of the following functions in the extrinsic control of GFR: renin–angiotensin mechanism, natriuretic peptides, and sympathetic adrenergic activity
  • Describe how each of the following works to regulate reabsorption and secretion, so as to affect urine volume and composition: renin–angiotensin system, aldosterone, antidiuretic hormone, and natriuretic peptides
  • Name and define the roles of other hormones that regulate kidney control

Several hormones have specific, important roles in regulating kidney function. They act to stimulate or inhibit blood flow. Some of these are endocrine, acting from a distance, whereas others are paracrine, acting locally.

Renin–angiotensin–aldosterone

Renin is an enzyme that is produced by the granular cells of the afferent arteriole at the JGA. It enzymatically converts angiotensinogen (made by the liver, freely circulating) into angiotensin I. Its release is stimulated by prostaglandins and NO from the JGA in response to decreased extracellular fluid volume.

ACE is not a hormone but it is functionally important in regulating systemic blood pressure and kidney function. It is produced in the lungs but binds to the surfaces of endothelial cells in the afferent arterioles and glomerulus. It enzymatically converts inactive angiotensin I into active angiotensin II. ACE is important in raising blood pressure. People with high blood pressure are sometimes prescribed ACE inhibitors to lower their blood pressure.

Angiotensin II is a potent vasoconstrictor that plays an immediate role in the regulation of blood pressure. It acts systemically to cause vasoconstriction as well as constriction of both the afferent and efferent arterioles of the glomerulus. In instances of blood loss or dehydration, it reduces both GFR and renal blood flow, thereby limiting fluid loss and preserving blood volume. Its release is usually stimulated by decreases in blood pressure, and so the preservation of adequate blood pressure is its primary role.

Aldosterone, often called the “salt-retaining hormone,” is released from the adrenal cortex in response to angiotensin II or directly in response to increased plasma K + . It promotes Na + reabsorption by the nephron, promoting the retention of water. It is also important in regulating K + , promoting its excretion. (This dual effect on two minerals and its origin in the adrenal cortex explains its designation as a mineralocorticoid.) As a result, renin has an immediate effect on blood pressure due to angiotensin II–stimulated vasoconstriction and a prolonged effect through Na + recovery due to aldosterone. At the same time that aldosterone causes increased recovery of Na + , it also causes greater loss of K + . Progesterone is a steroid that is structurally similar to aldosterone. It binds to the aldosterone receptor and weakly stimulates Na + reabsorption and increased water recovery. This process is unimportant in men due to low levels of circulating progesterone. It may cause increased retention of water during some periods of the menstrual cycle in women when progesterone levels increase.

Questions & Answers

What is the difference between regional anatomy and systematic anatomy?
Andrew Reply
Regional anatomy is the study of the interrelationships of all of the structures in a specific body region, such as the abdomen. ... In contrast, systemic anatomy is the study of the structures that make up a discrete body system—that is, a group of structures that work together to perform a unique
Tammy
so meaning of dissect
Mary Reply
it is the dismembering or the cutting of living organism to study the anatomical structure of it body
Kwasi
what are lymph nodes
Memory Reply
what is the best book that shows unit 1 about cell unit 2 about tissue unit 3 about embroyology
Abraham Reply
2
Hellen
to understand structure of body able to understand function of system. to understand how to build human body and function
Dereje Reply
hi
Neela
to determine body structures
Petra Reply
to know the use of each and every part of our body
Petra
to understand how our body structures work to support our lives
Petra
Is this a question?
Tammy
So what was the question?
Thamie
All the body work together to make the whole organism life possible
Kwasi
what is the importance of conversation
Hellen
To be able to identify the parts of the body and their functions
Hodasi
ok
Hodasi
Ideas are shared during conversation also informations are given
Hodasi
it reduces cost
Kwasi
what is carbon dioxide respiratory system why?
Prachi Reply
Carbon dioxide (CO2) is involved with the chemical process of cellular respiration. It is produced as a cellular waste product during the decomposition reactions and serves an important role in maintaining the appropriate acid-base balance in the body.
Tammy
thank you
Prachi
You're welcome!
Tammy
i have not under stood human heart
Simbwa Reply
means?
Dilshan
why a man became wild at the time of sexual intercourse. reason?
Soul
what is anatomy
philemon Reply
what is anatomy in terms of medicine
philemon
it is the study of human and animal form by observing and examined them and sometimes dissecting them and view the tiny thing by the use of microscope
Kwasi
anatomy is simply the scientific study of the body's structures
Petra
study of human body and animal
Crystal
why a man becomes wild at the time of sexual intercourse
Soul
Anatomy is the study of structure of the human body.
Tammy
Physiology is the study of the functions of the human body
Tammy
what is the difference between regional anatomy and systematic anatomy?
Andrew
Describe early studies into the working of human body.
Tonny Reply
please guys help me to answer this question; Define the two divisions of the skeleton ?
Jonathan Reply
two example of appendicular skeleton
Jonathan
upper limb ;eg humerus n lower limb;eg tibia
BRIAN
write notes on the level of organizations of the body .citing examples for each level
Kaddijatou Reply
Jonathan Nyakpaab
Jonathan
what is pathology
Ericka Reply
1 What is Nasogastric Tube 2 what is the difference between Nasogastric Aspiration and Nasogastric Feeling
ONOJA Reply
You measure a patient’s blood pressure at 130/85. Calculate the patient’s pulse pressure and mean arterial pressure. Determine whether each pressure is low, normal, or high.
ONOJA
normal blood pressure 120/80
Mohd
what are nocciceptors
Soul
hfjfjcjjjghkbv
Mohd
1 Its a flexible tube of plastic that pass through the nose, down to the eausophagus, and into the stomach, used to add or remove substances in the stomach.
Andile
2 Nasogastric aspiration is process of draining stomach contents via a tube and Nasogastric feeding is a process of giving food liquid through nasogastric tube
Andile
andile sir what is meant by clonoscopy
Soul
colonoscpopy is an exam use to detect abnormalities in the small intestine or the colon
Kwasi
What is the skin
Astony Reply

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Source:  OpenStax, Anatomy & Physiology. OpenStax CNX. Feb 04, 2016 Download for free at http://legacy.cnx.org/content/col11496/1.8
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