The biochemical effects of clenbuterol: with particular reference to taurine and muscle damage.

Administration of clenbuterol to rats in the drinking water over a 4 day period increased incorporation of [3H]leucine into muscle protein and caused a slight reduction in urinary 3-methylhistidine but did not result in an increase in body or muscle weight. However, both urinary and liver taurine were significantly reduced at the highest dose of clenbuterol (2 mg.kg-1.day-1). Serum creatine kinase, muscle isoenzyme (CK-MM) was raised and single muscle fibre injury was observed in the soleus muscle in animals treated with the middle dose (0.2 mg.kg-1.day-1) and highest dose (2 mg.kg-1.day-1). The reduction in the body pool of taurine caused by clenbuterol is of concern as taurine has been shown to have protective properties.