Myoglobin is a protein that is examined through a simple blood sample. Together with troponin it is one of the most used markers to confirm or exclude a possible heart damage. But not only. Here are all the functions and values ​​of Myoglobin. What is Myoglobin
Myoglobin is a globular protein whose main task is to convey oxygen to the mitochondria present in the cells of the muscle tissue. Consequently it is found in large quantities in the muscles. Its color is red, a hue given by the presence of EME.
- Deepening: what is a globular
protein A globular protein is a protein made up of peptide chains wrapped around themselves, forming a compact spherical shape – a sort of globe. Term from which it takes its name. Generally these proteins are soluble in water forming a colloid. Hemoglobin is also part of the globular proteins.
Myoglobin and heme group
As mentioned, myoglobin is composed of a chain of peptides – it also contains a heme group. The latter has an iron atom that has the ability to bind to oxygen. In this way, once this component is associated with Myoglobin, it can carry oxygen to the muscle fiber cells.
- A curiosity
The iron ion has a very particular structure that can be included in a sort of container that prevents water infiltration. This is one of mother nature’s tricks that allow you to avoid the dreaded oxidation.
Why Myoglobin is a marker of cardiac damage
In case of cardiac damage, the ischemic tissue, being in a condition of lack of oxygen, releases abnormal quantities of Myoglobin to counteract the insufficiency of this element. This is the reason why when high Myoglobin values ​​are detected, there is evident cardiac suffering in progress. The only drawback: the times to evaluate it are relatively short, because it tends to be reduced in the blood within a few hours thanks to the excretion of this substance through the kidneys. Did you know …
Myoglobin can also be evaluated with a urine test CK, Myoglobin and Troponin
Basically, Myoglobin behaves like Troponin: it rises within a few hours of the cardiac event – in this case on average 2 or 3 – it peaks after about ten hours and then drops completely within 24 hours. Thankfully, Troponin remains unchanged for about 10-15 days and Creatine Kinase for three to four. In this way, the three surveys can provide important data about the presence of heart damage in progress. Myoglobin: normal
values ​​Normal myoglobin values ​​are: 085 mg / ml When to worry
If you have typical symptoms of a heart attack such as chest pain and breathing difficulties, it is important to ask the emergency room doctors for the blood values ​​of Myoglobin associated with Troponin and Creatine Kinase (CK-MB). If myoglobin (and other) values ​​are elevated within 24 hours of the onset of symptoms it is very likely that there is a heart attack in progress. On the other hand, it is essential to check the trend of the values: if the decrease in hemoglobin is very timely it is possible that the cardiac lesion is limited, while if the values ​​remain stable for more hours it is probable that the lesion is more severe or in worsening. High myoglobin: it is always heart damage
No. Elevated myoglobin values ​​are not necessarily associated with heart damage, although they are most likely required for this purpose. However, if they are associated with high Troponin and high CK-MB, they are almost certainly so. Causes of high myoglobin
Heart
attack Muscle injury
Excessive intramuscular injections
Myositis
Muscle trauma
Surgery
Muscular dystrophy
Hyperthermia
Rhabdomyolysis
Muscle ischemia
High troponin and normal values. The test that tells you if you are at risk of heart attack Scientific sources
[1] Myoglobin blood test – MedLine Plus
[2] J Exp Biol. 2004 Sep;207(Pt 20):3441-6. Myoglobin: an essential hemoprotein in striated muscle. Ordway GA, Garry DJ.
[3] Myoglobin – PubMed Health Glossary
[4] Adv Exp Med Biol. 2007;618:181-93. Molecular insights into the functional role of myoglobin. Garry DJ, Mammen PP.
