A patient, waiting to undergo his cardiac surgery, is lying on a surgical platform. An
anesthesiologist enters the surgical room and injects some general anesthetics into the
patient’s bloodstream. The patient appears normal until after a few minutes, the patient
suddenly experiences increasing body temperatures leading to a high fever, muscle
rigidity, and increased heart rate. The anesthesiologist is perturbed, runs out of the
surgery room, and alerts the surgical staff of the patient’s alarming symptoms. The
surgical staff identifies the symptoms as Malignant Hyperthermia. What exactly is
Malignant Hyperthermia and how is it caused? Malignant Hyperthermia, a rare skeletal
muscular disease found in humans, pigs, horses, and many other animals, is a
channelopathy caused by abnormal calcium channels. This paper serves to investigate the
problems within the specific ion channels known to cause the disease. The goal of the
paper is to understand more about Malignant Hyperthermia and about how particular ion
channels associated with the disease operate. Learning about the chemistry behind the
disease is crucial in order to prevent future occurrences of Malignant Hyperthermia and
to design new treatments.
Malignant hyperthermia is a fatal, inherited disorder that affects less than 200,000
people in the United States.  As mentioned in the abstract, Malignant Hyperthermia is
channelopathy, or a disease caused by mutations in channel protein genes. Malignant
Hyperthermia is triggered by anesthetics, which includes common inhalants, and by
medication containing succinylcholine, a substance often used as a muscle relaxant in
emergency medicines.  After the initial trigger, life-threatening symptoms ensue. These
symptoms include overly active metabolism in skeletal muscles, muscle contraction and
rigidness, rising body temperature, and difficulty removing carbon dioxide from the body.
 Temperature can rise 1 C for every 5 minutes; hence, the word hyperthermia is
included in disease’s name.  If not treated immediately, death is a possible consequence.
Before we discuss the causes of
malignant hyperthermia, we must first
understand some background information about
calcium ion channels and the path the calcium
ions involved travel during muscle contraction.
For this process, refer to figure 1. First, an
action potential (nerve impulse) from a
sodium/potassium channel is triggered.  The
action potential reaches the T-tubule. . The T
tubule (traverse tubule) is a deep fold of the cell
membrane that contains many L-type calcium
channels (also known as Dihydropyridine receptors).  L-type calcium channels are
voltage-gate channels that regulate the flow of Ca2+.  The action potential causes an
electrical difference near the L-type calcium channels and activates them.  As a result,
the L-type calcium channels open and allow Ca2+ ions to flow into the...