I've mentioned this lab before in a previous post, but it has come around again this semester: Thermoregulation.
One of the down sides is that I have to take students blood (just a little finger prick), but despite my masochistic tendencies I dislike causing others pain, so I really want to make sure I know what I am doing before having to stab a student. Consequently, I practice on myself several times.
First I practiced testing blood glucose (mine was 94 on Monday after eating excessive amounts of rice and pumpkin cookies, thank you insulin and insulin receptors, keep up the good work!)
Then I tested my hematocrit levels by collecting some blood and centrifuging it. When centrifuged, the red blood cells and the plasma separate, like so:
When you get more dehydrated, the plasma (the pinkish colored part) decreases in relationship to the red blood cells (dark red section). This is called hemoconcentration. Some athletes use this to their advantage through the process of "blood doping" by injecting themselves with red blood cells to increase the percentage of red blood cells (RBCs) to total blood volume, thus having more RBCs to carry oxygen to cells/pick up waste as they exercise. This is illegal in professional sports.
I personally love centrifuging my blood (weird?) because as I frequently mention, I am chronically dehydrated. After my kidney infection I have been REALLy trying to stay hydrated, so I was quite excited to see that my plasma volume was actually greater than my RBC volume (which I guess would be bad if I was an athlete, but at least I am not dehyrdated!)
Another reason I always practice on myself before hand is that I am an excellent bleeder. My body loves to bleed. I could just bleed and bleed all day if I let myself- which can be a negative quality- but is convenient for having blood drawn, and for demonstrating hemoconcentration to my class! This is especially good because most people, in my experience, are not good bleeders, and I always have difficult getting an adequate sample from students.
At any rate, My fingers really hurt from my multiple pricks, so I shall stop typing, but go drink some water and increase your plasma volume!