History
The deficiency was the first metabolic myopathy to be recognized, when Dr. McArdle described the first case in a 30-year-old man who always experienced pain and weakness after exercise. Dr. McArdle noticed this patient’s cramps were electrically silent and his venous lactate levels failed to increase upon ischemic exercise. (The ischemic exercise consists of the patient squeezing a hand dynamometer at maximal strength for a specific period of time, usually a minute, with a blood pressure cuff, which is placed on the upper arm and set at 250 mmHg, blocking blood flow to the exercising arm.) Notably, this is the same phenomenon that occurs when muscle is poisoned by iodoacetate, a substance that blocks breakdown of glycogen into glucose and prevents the formation of lactic acid. Dr. McArdle accurately concluded that the patient had a disorder of glycogen breakdown that specifically affected skeletal muscle. The associated enzyme deficiency was discovered in 1959 by W. F. H. M. Mommaerts et al.
Read more about this topic: Glycogen Storage Disease Type V
Famous quotes containing the word history:
“[Men say:] “Don’t you know that we are your natural protectors?” But what is a woman afraid of on a lonely road after dark? The bears and wolves are all gone; there is nothing to be afraid of now but our natural protectors.”
—Frances A. Griffin, U.S. suffragist. As quoted in History of Woman Suffrage, vol. 4, ch. 19, by Susan B. Anthony and Ida Husted Harper (1902)
“We don’t know when our name came into being or how some distant ancestor acquired it. We don’t understand our name at all, we don’t know its history and yet we bear it with exalted fidelity, we merge with it, we like it, we are ridiculously proud of it as if we had thought it up ourselves in a moment of brilliant inspiration.”
—Milan Kundera (b. 1929)
“The history of persecution is a history of endeavors to cheat nature, to make water run up hill, to twist a rope of sand.”
—Ralph Waldo Emerson (1803–1882)