Question

Question 155 pts

Essay: Myasthenia gravis is an autoimmune disease that results in the destruction of acetylcholine (ACh) receptors. Its symptoms include systemic muscle weakness plus swallowing and speech difficulties. Discuss how the lack of ACh receptors would cause these effects

Answer 1

Answer:-

1. Myasthenia gravis is an autoimmune disorder in the body produces antibodies which are directed towards acetylcholine receptors specific for acetylcholine.
2. Acetylcholine is a neurotransmitters that is released from a neuronal terminal in order to relay information to a target cell to initiate a response.
3. In this case, Acetylcholine interacts with specific receptors that are located on the muscle cells.
4. Antibodies are produced by the immune system to fight and destroy foreign antigens entering the body. In case of this condition, the size of the thymus is seen to be relatively larger which indicates the possibility of involvement of the gland in this condition due to its role in immune response.
5. These autoantibodies destroy the receptors due to which the muscular response is weak and hence the muscles are not able to initiate the required activity or to bring about muscle contraction.
6. Muscle weakness occurs as cells are not able to undergo contraction due to lack of integration of signal thereby leading to muscle weakness only to be healed after a brief period of rest.
7. Swallowing and speech are the two activities that are associated with muscular contraction. These include the muscles associated with throat and tongue. Lack of contractile activity leads to problems during swallowing the food as it won't be pushed forward.