Urinary Hormone responses

Initial Post:

Urinary Hormones

1. Tell us about 3 urinary hormones. 

I. Choose one (1) hormone from the RAA system (Renin, Angiotensin II or Aldosterone)

II. Choose either Antidiuretic Hormone or Parathyroid hormone

III. And everyone will discuss Atrial Natriuretic peptide

2. For each of your 3 chosen hormones, tell me: 1) What triggers its release? 2) The specific part (s) of a nephron it affects and HOW?

 

I. Aldosterone is a steroid hormone secreted by the cortex of the adrenal glands. Aldosterone is triggered by high positive potassium ions in the extracellular fluid. It binds to receptors in both the distal tubules and collecting ducts for sodium conservation in the kidneys.

II. ADH and vasopressin are two other names for the antidiuretic hormone. It is produced by neurons of the supraoptic nucleus of the hypothalamus and stored in the posterior pituitary gland. It is triggered by a hyperosmolar state as your body is trying to rid itself of excess blood sugar by passing it into the urine. ADH moves from the peritubular capillaries and binds to ADH receptors in the plasma membranes of the distal convoluted tubule cells and the collecting duct cells. When it binds to that receptor a G protein mechanism is activated, which in turn activates adenylate cyclase.

III. Atrial Natiuretic peptide is secreted from the cells in the right atrium of the heart when they are stretched more than normal. It causes reduction in expanded extracellular fluid (ECF) volume by increasing renal sodium excretion. It is triggered by the atrial stretch. Decreased ADH decreases water reabsorption by the distal convoluted tubules and collecting ducts. Less water returns to the blood and more water is lost in the urine, which decreases blood volume.

 

Fluid Balance

Swelling occurs due to improper fluid balance. Apply what you learned from Chapter 27 to explain, compare and contrast Weeping Edema vs Lymphedema .

Be sure to include

· How each disorder relates to fluid balance

· Which body fluid compartments are compromised

· You should also include/define  the following terms in your post as you explain the disorders:

. Intracellular fluid

. Extracellular fluid

. Blood Plasma

. Interstitial fluid

. Cytosol

 

The medical term for swelling is edema. Weeping edema is when the swelling has become so severe that fluid starts to leak out of the skin. Weeping edema is usually a symptom of a disease. There is an accumulation of abnormal fluid in the interstitial tissues. Interstitial fluid is the main component of extracellular fluid and is present in between the cell spaces, they are rich in salt, ions, neurotransmitters etc. Interstitial fluid combined with blood plasma makes up the extracellular fluid. Blood plasma is the yellowish liquid component of blood that holds the blood cells in whole blood in suspension.

 

The body naturally allows fluid to leak from the blood vessels into the surrounding tissue as a means of transportation from blood to cells. Most of the fluid (about 90%) is reabsorbed back into the capillaries, while the remainder is absorbed by the lymphatic system. There is a fine balance between the fluid leaking from the capillaries and the fluid being reabsorbed back into the capillaries and lymphatic system. When there is a change in the volume of fluid leaking or being reabsorbed, an imbalance occurs, and this may eventually lead to swollen legs that can start to leak outside the body. Identifying the cause of this change is important to resolving weeping edema.

 

                  Lymphedema is most commonly caused by the removal of or damage to your lymph nodes as a part of cancer treatment. It results from a blockage in your lymphatic system, which is part of your immune system. The blockage prevents lymph fluid from draining well, and the fluid buildup leads to swelling. Intracellular fluid, also known ascytosol, is the fluid present inside of the cells and is rich in protein and amino acids.