Erythropoetine

Physiology function

Erythropoetine is glycoproteine that along with carbohydrate component contains 165 amino-acids in its composition. Erythropoetine is an endogene substance, that is in normal conditions synthetized mostly by activity of renal tissue. Uncompareble lower production comes from other tissues(liver). Basic function of this glycoproteine is stimulation of the erythropoesis process(erythrocyte production) in bone marrow. If organism creates huge amounts of erythropoetine, erythrocyte production can be 8-10 times bigger than normal. Erythropoesis stimulation by the influence of this substance, is mostly done on the level of pracell and bone marrow haemmocytoblast. Hard renal disease or missing of these organs are followed by hard types of anemia.

Today erythropoetine, by appliance of specified technologies, is synthetized on animal tissues and cell culture. The discovery of this type of erythropoetine, that is identic to endogene, solved problems with anemia.

Erythropoetine is allowed on market since 1985.

Appliance in sports

Appliance of synthetized erythropoetine in sport started in 1989. It is thought that huge number of athletes use this substance, especially in endurance sports. In soccer, this substance is used if there is a long-lasting league that lasts for more than 3 months per half-season, with tight schedule. These type of abuse is sometimes done with doctor assistance. These players usually have abnormal aerobic endurance and aerobic values. Out of soccer, this substance is mostly used in cycling, by some researches even 60-70% of cyclers use this substance.

These substance is applied 6-8 weeks before important sports competition. After one week of use stop, erythropoetine use is impossible to be proved. There is also other type, when this substance is taken in the start of the season. As season goes further and further, this player’s stamina constantly grows.

It is thought that erytropoetine abuse increases erythrocytes number 15-20%. Result is increase in capacity of blood for oxygen transport of approximately 6-8%.

Harmful effects

All harmful effects are the result of increased viscosity and blood hematocrit, with all consequences that follow these disorders. The biggest health damages that can be made are heart and brain attack.

Detection

There is not yet the test that can 100% determine presence of erythropoetine in blood. One of the most used tests is determination of hematocrit and haemoglobine concentration in blood. It is thought that average hematocrit at grown male is 38-46, and in some competitions top limit is 50. Values over 50 are conformation of erythropoetine use.

As top limit for haemoglobine concentration in plasma is intaked value of 16g/dl for women, and 18.5g/dl for males, athletes. It is known that altitude preparations can be very effective in increase of erythrocyte level. However, to determine true haematocrit value, blood should be taked from an athlete in the morning, before breakfast, in sitting position.

Direct technique is electrophoresis. Indirect techniques that are performed today, have a goal to determine value on base of erythrocyte volume and haemoglobine composition inside of them.

“Doping in sport”, Marina Djordjevic Nikic