 Hey everybody, Dr. O. We just got done talking about how the respiratory system plays a big role in maintaining acid-based balance, primarily by determining how much carbon dioxide and hence how much carbonic acid is in your body. Now we're going to look at the renal mechanisms and this has primarily has to do with the buffers, primarily by carbonate. So think about CO2 carbonic acid with the lungs, with the kidneys, we're primarily think about the buffer by carbonate. So let's go ahead and take a look here. If you develop an acidosis, which I've already explained several times why that's more common. So if the pH is dropping too low, what role are the kidneys going to play? And you can overthink this, but simply put, if you're too acidic, you've got to get rid of hydrogen ions. So what your kidneys will do is actually secrete hydrogen ions. So if you're acidotic, your pH is too low, then your kidneys will secrete more hydrogen ions. They'll buffer fluids there as well, but then they will reabsorb by carbonate. So that's the key right there. If your pH is too low, you're going to get rid of more hydrogen ions, which will bring the pH up and you're going to conserve or reabsorb more by carbonate the buffer. That's what your body does if you have an acidosis condition where your pH is too low. That's what your kidneys do. With an alkalosis condition, if your pH is too high, the opposite will happen. Your body will stop getting rid of acid, stop getting rid of hydrogen ions. It will actually start to get rid of by carbonate the buffer instead. So acidosis, you get rid of acids and you reabsorb buffers. Alkalosis, you get rid of buffers and you reabsorb acids. Now it's a little more complicated than that. In an alkalosis condition, yes, you would stop releasing so many hydrogen ions. You would also stop reclaiming the carbonate. We've already said that. But a third thing that would happen is it would actually, a strong acid, would be released into the paratubular fluid and would help bring the pH back down. So if your pH is too low, your lungs are going to get rid of carbon dioxide because it's an acid. Your kidneys are going to get rid of hydrogen ions. If your pH is too high, then your lungs are going to conserve carbonic acid, conserve carbon dioxide and your kidneys are going to get rid of buffers and conserve and keep the hydrogen ions. So that's the role that the kidneys, those are going to be the renal mechanisms that help maintain your acid base balance. And the two work together. So as we'll see in just a little bit when we start to talk about the disorders, you'll see that your kidneys will try to compensate for respiratory problems. Your lungs will try to compensate for metabolic problems as well. Okay. I hope this helps. Have a wonderful day. Be blessed.