Kelly Adams Yoho
October 5, 2009
Amyotrophic Lateral Sclerosis
The muscular system is made up of a group of highly specialized tissues that enable the body and its parts to move. The human body contains more than 650 different muscles, each performing voluntary and involuntary movements. Each muscle fiber is connected to a nerve cell called a motor neuron, which extends from the brain or the spinal cord. When stimulated by a motor neuron, muscle fibers will contract. Being able to move is an essential activity of the human body. (1)
Amyotrophic lateral sclerosis (ALS), also know as Lou Gehrig's disease is a rapidly progressive, fatal neurological disease that gradually kill the nerve cells located in the brain, brainstem and spinal cord. These nerve cells serve as a communication link between the nervous system and the voluntary muscles in the body. In ALS, these nerve cells die and are unable to send messages to the muscles. Eventually the patients lose their ability to move their arms, legs, and body. ALS does not impair the mind or intelligence, ability to see, smell, taste, hear, or recognize touch.
It is estimated that 5,000 people are diagnosed with ALS in the United States each year. It is considered one of the most common neuromuscular diseases in the world and affects people of all races. It is most common in people between the age of 40 and 60 years, and more men are affected than women. There are no clearly associated risk factors for contracting ALS, although 5 to 10 percent are inherited where one parent carries the gene responsible for the disease.
No one knows the causes of ALS or why it strikes certain individuals. However, in 1993, scientists discovered that mutations in the gene that produces the enzyme known as superoxide
dismutase 1(SOD1), was sometimes associated in the cases of familial ALS. Animal studies and laboratory tests have determined that ALS patients have higher levels of glutamate,...