Posts tagged kidneys

julieyumi: My old Anatomy student also asked for a clarification of the nephron.  Doodled this using my second semester notes + First Aid 2010 as reference.  (Click on the image to see a larger version.)

julieyumi:

My old Anatomy student also asked for a clarification of the nephron.  Doodled this using my second semester notes + First Aid 2010 as reference.  (Click on the image to see a larger version.)

Made this on Microsoft Powerpoint to remind myself of the four functions of steroids (aka glucocorticoids). Steroids are made in the adrenal glands, which are glands that sit above the kidneys. The adrenal gland is also in charge of producing the hormones epinephrine (also called adrenaline) and norepinephrine (noradrenaline), which provide you with an “adrenaline rush” in times of stress. When you’re stressed out, epinephrine and norepinephrine kick in to increase your heart’s pumping ability so blood can circulate better to vital parts of the body, provide energy to the cells by breaking down protein and fat, inhibiting insulin so more glucose is available in the blood for energy, and altering your mood by increasing alertness. As stated on Medline Plus, steroids are used to treat:  Arthritis Asthma Autoimmune diseases such as lupus and multiple sclerosis Skin conditions such as eczema and rashes Some kinds of cancer That is because steroids can decrease inflammation. In addition, steroids can also decrease serum calcium and decrease cerebral edema! Sources:http://www.nlm.nih.gov/medlineplus/steroids.htmlhttp://www.britannica.com/EBchecked/topic/190049/epinephrine-and-norepinephrine

Made this on Microsoft Powerpoint to remind myself of the four functions of steroids (aka glucocorticoids). Steroids are made in the adrenal glands, which are glands that sit above the kidneys. The adrenal gland is also in charge of producing the hormones epinephrine (also called adrenaline) and norepinephrine (noradrenaline), which provide you with an “adrenaline rush” in times of stress.

When you’re stressed out, epinephrine and norepinephrine kick in to increase your heart’s pumping ability so blood can circulate better to vital parts of the body, provide energy to the cells by breaking down protein and fat, inhibiting insulin so more glucose is available in the blood for energy, and altering your mood by increasing alertness.

As stated on Medline Plus, steroids are used to treat:

  •  Arthritis
  • Asthma
  • Autoimmune diseases such as lupus and multiple sclerosis
  • Skin conditions such as eczema and rashes
  • Some kinds of cancer

That is because steroids can decrease inflammation. In addition, steroids can also decrease serum calcium and decrease cerebral edema!

Sources:
http://www.nlm.nih.gov/medlineplus/steroids.html
http://www.britannica.com/EBchecked/topic/190049/epinephrine-and-norepinephrine

In ‘n’ out. Straight catheterization.

Renaaaal.

Even though I’m supposed to be reviewing pulmonary and neurologic disorders. What am I doing? I don’t know, but I thought this was interesting.

Nice explanation of acidosis and alkalosis!

It’s difficult for me to remember all the steps of RAAS, or the Renin-Angiotensin-Aldosterone System. But this cute little diagram (snatched from Wikipedia) serves as a spiffy reminder. But what’s the point of “RAAS”? Two important things: blood volume and blood pressure regulation. When blood pressure begins to drop, the kidneys detect this and decide to initiate a defense mechanism—the release/secretion of an enzyme called renin. This special enzyme then floats around the blood and converts inactive angiotensinogen (a precursor peptide in the blood) into angiotensin I. Angiotensin I is a protein in the blood that causes blood vessels to constrict… but only to a minimal extent. For a more profound effect, angiotensin I is sent to the lungs, the home of an enzyme named ACE (Angiotensin Converting Enzyme). Angiotensin II is the product—a stronger hormone that can deliver more powerful changes in blood pressure (namely, an elevation in blood pressure). Angiotensin II can work directly on the blood vessels to cause blood pressure increases through vasoconstriction (essentially, forcing the diameter of the blood vessels to shrink so the blood inside will create more friction against the wall of the vessel, which increases blood pressure). But something even more amazing that angiotensin II can do is stimulate the release of aldosterone. How does it do this? By going over to the adrenal cortex (a part of the adrenal endocrine glands that sit comfortably above the kidneys like a Santa Claus hat) and stimulating the release of aldosterone, a hormone. So what does aldosterone do?? It goes to the kidney and says, “You have to reabsorb sodium and water and release potassium. This way, blood volume goes up again!” And so, your body’s blood pressure and blood volume is under control again… All thanks to RAAS!

It’s difficult for me to remember all the steps of RAAS, or the Renin-Angiotensin-Aldosterone System. But this cute little diagram (snatched from Wikipedia) serves as a spiffy reminder.

But what’s the point of “RAAS”? Two important things: blood volume and blood pressure regulation.

When blood pressure begins to drop, the kidneys detect this and decide to initiate a defense mechanism—the release/secretion of an enzyme called renin. This special enzyme then floats around the blood and converts inactive angiotensinogen (a precursor peptide in the blood) into angiotensin I. Angiotensin I is a protein in the blood that causes blood vessels to constrict… but only to a minimal extent. For a more profound effect, angiotensin I is sent to the lungs, the home of an enzyme named ACE (Angiotensin Converting Enzyme). Angiotensin II is the product—a stronger hormone that can deliver more powerful changes in blood pressure (namely, an elevation in blood pressure). Angiotensin II can work directly on the blood vessels to cause blood pressure increases through vasoconstriction (essentially, forcing the diameter of the blood vessels to shrink so the blood inside will create more friction against the wall of the vessel, which increases blood pressure). But something even more amazing that angiotensin II can do is stimulate the release of aldosterone. How does it do this? By going over to the adrenal cortex (a part of the adrenal endocrine glands that sit comfortably above the kidneys like a Santa Claus hat) and stimulating the release of aldosterone, a hormone.

So what does aldosterone do?? It goes to the kidney and says, “You have to reabsorb sodium and water and release potassium. This way, blood volume goes up again!”

And so, your body’s blood pressure and blood volume is under control again… All thanks to RAAS!

Fascinated by the kidneys

Your body stores calcium in the bones, but also maintains a constant level of calcium in the blood. If the blood calcium level falls, then the parathyroid glands in your neck release a hormone called parathyroid hormone. Parathyroid hormone increases calcium reabsorption from the distal tubule of the nephron to restore the blood calcium level. Parathyroid hormone also stimulates calcium release from bone and calcium absorption from the intestine.

In addition to parathyroid hormone, your body also requires vitamin D to stimulate calcium absorption from the kidney and intestine. Vitamin D is found in milk products. A precursor to vitamin D (cholecalciferol) is made in the skin and processed in the liver. However, the final step that converts an inactive form of cholecalciferol into active vitamin D occurs in the proximal tubule of the nephron. Once activated, vitamin D stimulates calcium absorption from the proximal tubule and from the intestine, thereby increasing blood calcium levels.

Kidney stones are often caused by problems in the kidney’s ability to handle calcium. In addition, the kidney’s role in maintaining blood calcium is important in the bone disease osteoporosis that afflicts many elderly people, especially women.

As you can see, the kidneys perform many functions that are important to your body:

  • Controlling the composition of your blood and eliminate wastes—filtration/reabsorption/secretion method
  • Influencing blood pressure—renin secretion
  • Helping to regulate your body’s calcium—vitamin D activation

    From: http://health.howstuffworks.com/kidney8.htm