Research the causes of these diseases that are similar to, or related to, Autoimmune Urticaria: 1  Idiopathic urticaria without angioedema. 2  Chronic urticaria.  Occult infection (e.g., sinusitis, oral infection, cholecystitis, vaginitis, prostatitis, hepatitis, HIV, tinea manus or pedis)
The sarcoplasmic reticulum is known for its storage of calcium ions in muscle cells.
Calcium within a muscle fiber increases as action potentials are repeatedly and rapidly generated in the sarcolemma. As calcium accumulates within the cell, the strength of the muscle fiber contraction increases until maximal contraction is reached.