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.
The S.R. of the smooth muscle cell does not contain enough calcium to maintain contraction for long periods of time. How calcium starts the contraction process in smooth muscle: If you'll recall from the discussion of the biochemistry of smooth muscle cells, troponin is not found in smooth muscle.