Term
Where does aldosterone come from? |
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Definition
The adrenal cortex (same as cortisol) |
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Term
What are the major effects of aldosterone? (2) |
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Definition
It controls BP, and plasma volume. |
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Term
Where does aldosterone have it’s main effect? |
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Definition
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Term
What chemicals levels does aldosterone alter? |
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Definition
Sodium resorption and Potassium secretion. |
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Term
What chemical gets swapped for what chemical in the kidney? |
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Definition
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Term
If you get rid of K in the kidney, what happens in terms of Na and H2O? |
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Definition
If K is removed, Na is resorbed, H2O follows Na, so H2O is retained. |
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Term
What happens in terms of the aldosterone system if there is increased plasma potassium? |
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Definition
Aldosterone levels are increased à kidney secretion of K+ à Na+ resorptoin à increased H2O uptake |
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Term
Describe the renin – angiotensin – aldosterone system – what triggers it, why, and what is the end effect? |
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Definition
Decreased BP is detected in the kidney à renin production –> angiotensinogen à angiotensin1 àAngiotensin 2 à Adrenal cortex à aldosterone release à Decreased Na+ secretion (therefore increased H2O retention) à increased plasma volume à Increased BP à decreased renin production. |
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Term
Give some extreme examples that would trigger the R-A-A system. |
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Definition
Running a marathon and get dehydrated so BP drops, bleeding out w/ a large hemmorhage. |
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Term
What is antidiuretic hormone AKA? |
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Definition
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Term
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Definition
Posterior pituitary gland |
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Term
Where does ADH have its action? |
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Definition
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Term
What does ADH promote in the kidneys? |
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Definition
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Term
What triggers ADH release? |
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Definition
Inadequate fluid replacement – dehydration. |
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Term
What are the positive stimuli for ADH? (2major) |
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Definition
Decreased arterial plasma volume, and increased plasma molarity. |
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Term
Where are osmoreceptors located? |
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Definition
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Term
What happens if the osmoreceptors detect increased osmolarity? |
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Definition
The receptors fire, and send a signal to the hypothalamus to increase release of antidiuretic hormone, to increase H2O resorption in the kidney so that osmolarity will decrease. |
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Term
Signals from what two receptors will trigger the hypothalamus to release ADH? And where are the receptors located? |
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Definition
Osmoreceptors in the hypothalamus, and volume receptors in the left atrium. |
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Term
What is the effect of moderate to high intensity exercise on osmolarity and plasma volume? |
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Definition
Decreased plasma volume, and increased osmolarity. |
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Term
Calcium is important in areas other than the bones. What are some of them? (3 major) |
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Definition
Muscle, nerve function and clotting. |
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Term
Where is the majority of calcium stored? |
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Definition
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Term
What does parathyroid hormone control? |
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Definition
Release of Ca++ from the skeleton and gut. |
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Term
What is parathyroid hormone stimulated by? (2major) |
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Definition
Low plasma calcium and exercise. |
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Term
What are the effects of parathyroid hormone? (3major) |
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Definition
1. Release of calcium from bone, 2. Absorption of calcium from the kidneys, 3. Conversion of vitamin D3 into1.25 (OH)2D3 to facilitate absorption of calcium from the gut. |
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Term
Where does calcitonin come from? |
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Definition
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Term
What does calcitonin do? (major function) |
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Definition
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Term
What are the effects of calcitonin? |
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Definition
Blocks the release of calcium from bone, stimulates excretion of calcium from kidney. |
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Term
What stimulates calcitonin? |
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Definition
Increase in plasma calcium |
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Term
What is the major action of thyroid hormones (T3/T4) |
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Definition
They have a permissive effect on other hormones, giving them the OK to act w/ acid. They can also change the actions of other hormones. |
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Term
How can thyroid hormones alter the effectiveness of other hormones? (3major ways) |
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Definition
Change the number of surface receptors, change in rate or amplitude of receptor/hormone affinity, increase cAMP (helps when the hormone is not a steroid). |
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Term
What happens to BMR in the hypothyroid patient? |
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Definition
It decreases, which decreases energy and increases weight. |
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Term
What happens to BMR in the hyperthyroid pt? |
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Definition
It increases, which increases energy and decreases weight. |
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Term
What are T3 and T4 bound to? |
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Definition
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Term
How long after being released from the thyroid can the effects of T4 be seen? |
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Definition
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Term
Describe the cortical pathway that leads to the release of thyroid hormones. |
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Definition
Hypothalamus releases thyroid releasing hormone à Anterior pituitary, which releases Thyroid stimulating hormone, which goes to the thyroid à T3/T4 release. |
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Term
What controls thyroid hormones? |
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Definition
Negative feedback to the hypothalamus to turn of anterior pituitary, to the thalamus which will decrease release of the hormones. |
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