Calcium in muscle contraction

Soluble Compounds. The mechanism of barium toxicity is related to its ability to substitute for calcium in muscle contraction. Toxicity results from stimulation of smooth muscles of the gastrointestinal tract, the cardiac muscle, and the voluntary muscles, resulting in paralysis (47). Skeletal, arterial, intestinal, and bronchial muscle all seem to be affected by barium. 

Ruegg, J.C. (1988). Calcium in Muscle Contraction. 2nd edn., Springer-Verlag, Heidelberg. 

Riiegg, J.C. Calcium in muscle contraction. 2nd. ed.. Springer, Berlin Heidelberg New York (1992)... 

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