What Causes Diabetes?
Morgan Richards
What Happens in the Body
When Blood Glucose Rises
The pancreas releases insulin when blood glucose levels are high. Insulin is produced in beta cells in the pancreas. Insulin is then bound to insulin receptors on cell membranes and opens up the glucose transport channels. When the glucose channels are opened the glucose from the blood can enter the cells to be used for energy. Glucose is also stored in the liver and fat and muscle tissue as glycogen. Glycogen is many glucose molecules bonded together. After this process the body's blood glucose levels return to normal.
When Blood Glucose Lowers
When blood glucose levels go down the pancreas releases glycagon into the blood. Glycagon is produced by alpha cells in the pancreas. When released, glycagon signals the liver to convert stored glycogen into glucose. After glycogen is broken into glucose it is released into the blood and the body's blood glucose levels return to normal.
Type 1 Diabetes
In type 1 diabetes the beta cells and pancreas do not produce insulin. This causes the levels of glucose to remain high because they cannot enter the cells in the body.
Type 2 Diabetes
In type two diabetes the insulin receptors on cell membranes become resistant to insulin. The insulin in a body with type 2 diabetes cannot bond to the insulin receptors. This causes the glucose levels and insulin levels to be high.
What is Feedback
Homeostasis
Homeostasis is the normal state of the human body. The body is able to keep this steady state making necessary changes in the body in reaction to outside or internal changes. Feedback loops regulate a body's heart rate, temperature, and blood glucose levels by using two types of feedback: positive and negative.
Positive Feedback
One kind of feedback is positive feedback. This kind of feedback causes a body's action to increase.
Negative Feedback
The other kind of feedback is negative feedback. This kind of feedback causes the body to stop an action, or sometimes causes the opposite reaction.
How to Read Your Results
What Happens When You're Tested for Diabetes?
There are two tests patients must go through to determine if they have diabetes and if so what type. The two tests are glucose tolerance testing and insulin level testing. First the patient must not eat or drink anything for 12 hours. The patient's blood is drawn for a "normal" base level. The patient is then given a a concentrated sugar solution to drink. Blood is draw and observed for a certain measure of time. For each time the blood is observed the amount of glucose and insulin is recorded.
Glucose Tolerance Testing
This type of testing can determine wither or not a patient has diabetes. This test monitors the amount of sugar in the patient's plasma. In this case patient A and patient B have diabetes. Both patient A and patient B's glucose levels rose extremely high and did not return to their normal state. This means that both patients have a problem with the insulin in their body because glucose did not leave the blood stream to inside the cells.
Insulin Level Testing
Insulin level testing is used to determine the type of diabetes a patient may have. This test monitors the level of insulin in the patient. In this case patient A has type 1 diabetes and patient B has type 2 diabetes. Patient A's insulin levels did not change despite the increase of glucose which means the pancreas was not producing insulin. Patient B's insulin levels continued to rise along with the glucose levels but didn't lower. This means patient B's insulin receptors were not taking in insulin from the blood to open up glucose channels.