Myoglobin is a monomeric heme protein that is structurally related to hemoglobin. Very little free myoglobin is in circulation. It is synthesized and found predominantly in skeletal and cardiac muscle. During the course of a myocardial infarction (MI), myoglobin escapes from the ischemic cardiac muscle and can reach levels 5-10 times normal levels during the first 5-18 hours. A wide variety of pathological processes that damage skeletal muscles, cause release of myoglobin into the circulation. Muscle damage resulting in high levels of myoglobinuria is clinically referred to as rhabdomyolysis. Measurement of myoglobin in rhabdomyolysis may be useful to determine the likelihood of significant renal toxicity. A high serum myoglobin level associated with a low urine myoglobin clearance rate indicates high risk for renal failure. A high serum myoglobin level with high myoglobin clearance rate indicates low risk for renal failure. A relatively low serum myoglobin level indicates minimal risk for renal failure.
Swiss-Prot Accession Number: P02144