Myoglobin is a protein, or protein pigment, found in your heart and in the voluntary muscles that support your skeleton. If your muscle tissue gets damaged, this protein can accumulate in your bloodstream and travel to your kidneys. Inside your kidneys, myoglobin breakdown products can trigger the onset of several types of damage.
Myoglobin Basics
Myoglobin's main function inside your body is to provide your muscles with extra oxygen. When you exercise at a high intensity, you can deplete your muscles' oxygen supplies. Each myoglobin molecule has oxygen attached to it, and your muscles can draw on this reserve source to replenish themselves and maintain your exercise intensity for an extended period of time. Myoglobin is chemically similar to the protein called hemoglobin, which carries oxygen in your bloodstream. Both proteins contain a reddish-brown substance called heme, which gives them their ability to bind to oxygen in your body, as well as a distinctive color.
Myoglobin and Rhabdomyolysis
Myoglobin leaks into your bloodstream when you develop a condition called rhabdomyolysis. People with this condition have some sort of damage to their skeletal muscle tissues. Common causes or risk factors for this type of damage include traumatic muscle injuries, heat stroke, alcoholism, seizures, shaking chills, extreme physical exertion, muscle tissue death, the presence of certain genetic disorders and either use or overdose of a variety of drugs, including heroin, cocaine, PCP, amphetamines and cholesterol medications called statins.
Kidney Effects
When myoglobin proteins enter your bloodstream, they pass to your kidneys, which act as filters for a broad range of blood-borne substances. In turn, your kidneys will try to eliminate these proteins from your body in your urine. However, myoglobin produces breakdown products that can clog your kidneys' internal structures. If enough myoglobin passes through your kidneys, it can damage these structures and lead to severe problems that include kidney failure and a kidney-failure-triggering condition called acute tubular necrosis, which occurs when structures inside your kidneys, called tubules, don't get enough oxygen.
Treatments and Outcomes
If you develop rhabdomyolysis, your doctor may be able to prevent kidney damage by using high doses of IV fluids to flush your kidneys, according to the U.S. National Library of Medicine's Medline Plus. Your doctor may also need to artificially filter your blood with a technique called dialysis, or give you medications such as bicarbonate or diuretics. Many people with less severe cases of rhabdomyolysis recover and return to their normal routines within a period of weeks or months. However, people with more severe cases of the disorder can develop short-term kidney failure and/or long-term kidney damage. Ask your doctor for more information on myoglobin proteins, rhabdomyolysis and kidney problems.
