The Hormone Game

[fma08]

I'm bored, so since I'm studying the endocrine system in A&P... I decided to start up a little game. It's simple, you can put up a hormone, and someone else says where it comes from, what it does, etc. etc. being as specific as possible i.e. insulin lowers blood sugar ain't gonna cut it. Or put up a condition and how the endocrine system fixes it, i.e. hyperglycemia -> insulin released by.... etc.

I'll start with calcitonin.

GO!


Side note, we all know there are some people that recite these in their sleep *cough* rid *cough* appreciate it if ya give the youngins a chance first

 

[BossyCow]

Caltitonin produced by C cells in the thyroid gland. Calcitonin metabolizes calcium and phoshorus. It inhibits the activity of osteoclasts and also works in the kidneys to modulate the dumping of calicum and phosphorus in the urine.

Some links between the amount of calicum in the blood and the production of calcitonin by the thyroid.

Being used as a therapy for Pagets Disease and is being studied for use in treating osteoporosis.

 

[fma08]

Caltitonin produced by C cells in the thyroid gland. Calcitonin metabolizes calcium and phoshorus. It inhibits the activity of osteoclasts and also works in the kidneys to modulate the dumping of calicum and phosphorus in the urine.

Some links between the amount of calicum in the blood and the production of calcitonin by the thyroid.

Being used as a therapy for Pagets Disease and is being studied for use in treating osteoporosis.

Bonus points if you put up the other half of it's effects related to that, and your turn then to put up a condition or hormone ^_^

 

[medicdan]

Penial Gland-- Melatonin

 

[fma08]

Penial Gland-- Melatonin

Officially they don't know for sure. But they think that it is released by the piniocytes in the pineal gland after stimulation by light from the retina to regulate the circadian rhythms by causing drowsiness and lowering the body temp.

 

[fma08]

Atrial natriuretic peptide

 

[mycrofft]

Whispered aside

Make that primary known effects. We are finding out that many hormones affect us in multiple ways and systems. They make me uneasy because they are so very powerful in such small doses.

 

[Dobby]

Since I have suddenly found this sort of conversations very interesting I decided to research this specifc topic and though it might be of interest to relay the following :

Atrial natriuretic peptide (ANP), atrial natriuretic factor (ANF), atrial natriuretic hormone (ANH), or atriopeptin, is a protein (polypeptide) hormone secreted by heart muscle cells. Its involved in the homeostatic control of body water, sodium, potassium and fat (adiposity). It is released by muscle cells in the upper chambers (atria) of the heart (atrial myocytes), in response to high blood pressure. ANP acts to reduce the water, sodium and adipose loads on the circulatory system, thereby reducing blood pressure

ANP is a 28-amino acid peptide with a 17-amino acid ring in the middle of the molecule.ANP was discovered in 1981 by a team in Kingston, Canada led by Adolfo J. de Bold after they made the seminal observation that injection of atrial (but not ventricular) tissue extracts into rats caused copious natriuresis.

Production
ANP is produced, stored and released by cardiac myocytes of the atria of the heart. It is released in response to atrial stretch and a variety of other signals induced by hypervolemia, exercise or caloric restriction. The hormone is constitutively expressed in the ventricle in response to stress induced by increased afterload (eg. increased ventricular pressure from aortic stenosis) or injury (eg. myocardial infarction).

ANP is secreted in response to:

Atrial distention, stretching of the vessel walls
Sympathetic stimulation of β-adrenoceptors
Raised sodium concentration (hypernatremia)
Angiotensin-II
Endothelin, a potent vasoconstrictor

The atria become distended by high extracellular fluid and blood volume, and atrial fibrillation. Notably, ANP secretion increases in response to immersion of the body in water, which causes atrial stretch due to an altered distribution of intravascular fluid. ANP secretion in response to exercise has also been demonstrated in horses.


Receptors
Three cell surface receptors have so far been identified on which ANP act, and these are designated ANPA, ANPB and ANPC. The ANPA and ANPB receptors have guanylate cyclase activity & mediate the biological effects by producing cGMP.

The ANPC receptor functions mainly as a clearance receptor by binding & sequestering ANP from the circulation.

All natriuretic peptides are bound by the ANPC receptor. Atrial natriuretic peptide and brain natriuretic peptide act through the ANPA and C-type natriuretic peptide through the ANPB receptor


Physiological effects
ANP binds to a set of receptors. Receptor-agonist binding causes reduction in blood volume therefore reduction in cardiac output & systemic bp. Lipolysis is increased & renal sodium reabsorption is decreased. The overall effect of ANP on the body is to counter increases in blood pressure & volume caused by the renin-angiotensin system.


Renal
Dilates the afferent glomerular arteriole, constricts the efferent glomerular arteriole, and relaxes the mesangial cells. This increases pressure in the glomerular capillaries, thus increasing the glomerular filtration rate (GFR), resulting in greater excretion of sodium and water.
Decreases sodium reabsorption in the distal convoluted tubule and cortical collecting duct of the nephron.
Inhibits renin secretion, thereby inhibiting the renin-angiotensin system.
Reduces aldosterone secretion by the adrenal cortex.

Vascular
Relaxes vascular smooth muscle in arterioles and venules by.

Cardiac
Inhibits maladaptive cardiac hypertrophy.

Hope it was a bit of an interesting read . B)



.

 

[fma08]

Great read, and your turn ^_^

 

[Dobby]

Glad you liked it. Ok I have one Angiotesin. B)

 

[Dobby]

okay I have one angiotensin B)

 

[fma08]

In response to lowering blood volume blood pressure, the nephrons in the kidneys release renin into the blood which acts as a catalyst to convert angiotensinogen to angiotensin II, which targets smooth muscle in the arterioles in the nephrons to constrict, decreasing the loss of water through them thus slowing/stopping/reversing the decline of the blood pressure. It also promotes the release of aldosterone from the zona glomerulosa in the adrenal cortex which promotes the retention of ions, mainly sodium, from the urine, and indirectly with it, water, to raise the blood pressure. It also targets the cells in the proximal convoluted tubule in the nephron to retain Na+ and Cl- ions which promotes the retention of water from urine, thus increasing blood pressure.


Cortisol

 

[Shishkabob]

Jeez, this seals it, I need to take an A&P class...

I always knew I was good in science and biology, but I got lost within the first 3 lines of text in this thread.

 

[EMERG2011]

Cotisol is released by the adrenal gland in response to stress and anxiety. Commonly referred to as the "stress hormone" cotisol causes an increase in blood pressure as well as blood sugar in addition to a host of other systemic effects. Extended release of cortisol (as in Cushing's Syndrome) has been shown to cause rapid weight gain, muscle wasting, insomnia, irritability, and impotence.



Human Chorionic Gonadotropin Hormone