
November 4, 2002
Other
Question from St. Paul, Minnesota, USA:
If diabetes occurs due to beta cells being unable to produce insulin, why are there problems with low blood sugar that require treatment with a Glucagon Emergency Kit? Why can’t the body regulate the lows itself and just need assistance for the highs?
Answer:
As you know, the balance of blood glucose regulation hinges on many things — the most prominent are exercise, diet, and insulin. A number of other considerations play a role also (e.g., other hormones like growth hormone, thyroid hormone, cortisol, epinephrine, glucagon) as well as appropriate metabolism of other types of carbohydrates and proteins by the liver. There are other types of materials that help “shuttle” fuel (like sugar) into and out of cells to present the sugars into the cells to be used for energy. So the biochemistry is really quite complex.
Based on your question, I am assuming that the “lows” you refer to involve a so-called insulin reaction experienced by a person with known diabetes. These spells most often occur because the balance of insulin, food, and exercise gets off leading to relatively more insulin to food. Exercise by-passes many of the effects of insulin and hence acts as an “insulin-sensitizer” — in effect, allowing insulin to work more effectively.
Despite the variety of methods to provide insulin (combinations of long, intermediate, fast -acting insulins, and use of insulin pumps), we cannot mimic a normally functioning pancreas which would adjust the amount of insulin produced moment-to-moment. And when non-diabetic folks have low blood sugar (and everyone does on occasion), our bodies put in place a variety of manipulations to attempt to raise the glucose back up including (but not limited to):
We feel hungry.
We release cortisol and epinephrine (adrenaline) from the adrenal glands, glucagon from the pancreas, and growth hormone from the pituitary gland in the brain which act on the liver and muscles to cause release of stored glucose.
We breakdown a bit of fat to release the stored energy there.
We make less insulin.
The irritability and shakiness and sweatiness are generally systemic reflections of the epinephrine.
Well, clearly people with diabetes having a hypoglycemic episode experience all of this — except that they can’t turn down the insulin level since the shot is in. Even the dramatic event of a hypoglycemic seizure is in some way a compensatory response: the contractions of the muscles help breakdown and release stored sugar.
DS