|Register||Search||Today's Posts||Mark Forums Read|
|Peptide Forum Peptide Forum. Ask and discuss questions on peptide protocols, custom peptide synthesis, peptide identification and peptide sequencing.|
| ||LinkBack||Thread Tools||Display Modes|
Natriuresis is the process of excretion of abnormally large amounts of salt in the urine. The word comes from the Latin term natrium, which means "sodium" and the Greek term ouresis, which means "making water." Natriuresis is similar to diuresis, the excretion of an unusually large quantity of urine, except that in natriuresis the urine is exceptionally salty.
There are three naturally occurring protein hormones in the body that cause natriuresis. They are called A-type, B-type, and C-type natriuretic peptides (small protein molecules). These peptides lower the concentration of sodium in the blood, which tends to lower blood volume because the sodium takes water with it into the urine. Many diuretic drugs take advantage of this mechanism to treat medical conditions like high blood pressure. In fact, the natriuretic peptides are sometimes called the body's "natural diuretics."
Natriuretic peptides are produced by the heart and the blood vessels. The body produces more of them when it's affected by diseases -- like heart failure, kidney failure, and liver disease -- that are characterized by an expanded fluid volume. .
Re: Natriuretic peptides
Types of Natriuretic Peptides
A-type natriuretic peptides are also called atrial natriuretic peptides. They're made, stored and released largely by the atria, muscle cells in the upper chambers of the heart. The body makes more A-type natriuretic peptide in response to high blood pressure and stretching of the atria. These conditions are often seen in congestive heart failure, where increased blood volume and higher levels of extracellular fluid (fluid overload) stretch the heart's walls. In patients with heart failure, A-type natriuretic peptides are also made by the ventricles, cells in the heart's lower chambers -- the pumping chambers.
A-type natriuretic peptide causes a reduction in blood volume and therefore a reduction in heart output and blood pressure. Excretion of sodium by the kidneys and the breakdown of fat cells are also increased.
B-type natriuretic peptides are also called brain natriuretic peptides. B-type natriuretic peptides are made, stored and released mainly by the ventricles. It's produced in response to stretching of the ventricles due to the increased blood volume and higher levels of extracellular fluid (fluid overload) that accompany congestive heart failure. It acts as a natural diuretic, eliminating fluid, relaxing blood vessels and funneling sodium into the urine.
When your heart is damaged, your body secretes very high levels of B-type natriuretic peptide into your bloodstream in an effort to ease the strain on your heart. The levels may also rise if you have new or increasing chest pain (unstable angina) or after a heart attack.
C-type natriuretic peptides are produced by cells that line the blood vessels. They cause relaxation of blood vessels, helping to lower blood pressure. Unlike A-type and B-type natriuretic peptides, they don't have direct natriuretic activity.
Re: Natriuretic peptides
CNP [C-type natriuretic peptides],
however, is not natriuretic and is distinct in its properties. Peripheral effects include
(3) inhibition of the renin-angiotensin and aldosterone system, and
(4) anti-mitogenic effects on endothelial, smooth muscle and myocardial cells.
Central effects include
(1) thirst (water drinking) inhibition,
(2) inhibition of salt appetite,
(3) antipressor effects, and
(4) inhibition of the hormones ADH and ACTH
Re: Natriuretic peptides
B-type Natriuretic Peptide (BNP) blood test
BNP is a substance secreted from the ventricles or lower chambers of the heart in response to changes in pressure that occur when heart failure develops and worsens. The level of BNP in the blood increases when heart failure symptoms worsen, and decreases when the heart failure condition is stable. The BNP level in a person with heart failure – even someone whose condition is stable – is higher than in a person with normal heart function.
To test the BNP level,
A small amount of blood is taken and placed in a machine that detects the level of BNP in your blood. The test takes about 15 minutes. The BNP level helps to determine if you have heart failure, rather than another condition that may cause similar symptoms. In addition, BNP help the physician make decisions about hospitalizations, aggressive treatments, and future prognosis.
* BNP levels below 100 pg/mL indicate no heart failure
* BNP levels of 100-300 suggest heart failure is present
* BNP levels above 300 pg/mL indicate mild heart failure
* BNP levels above 600 pg/mL indicate moderate heart failure.
* BNP levels above 900 pg/mL indicate severe heart failure.
|natriuretic , peptides|
|Thread||Thread Starter||Forum||Replies||Last Post|
|Peptides how many is to many||Kwojcik||General Science Questions and Layperson Board||0||03-13-2012 06:45 AM|
|Which pH values would potentially provide the best separation of the three peptides?||andy||Peptide Forum||1||11-16-2011 06:43 AM|
|disulfide cleavage||dpar||Peptide Forum||5||08-20-2010 01:09 PM|
|Handling Peptides - Tips||moleculardude||Peptide Forum||0||09-05-2006 09:40 PM|
|New look for molecular photodiodes - helical peptides||Bubba Do Wah Ditty||Physics Forum||0||06-25-2004 12:06 PM|