1. A2 Biology Topic 7 Performance enhancing drugs

2. Banned substances and practices
Anabolic steroids
Stimulants
Hormone agonists
Hormones and releasing factors
Diuretics
Beta-2 agonists
Narcotics
Blood doping
Beta blockers
Gene doping
Is it an infringement of athletes human rights to be required to give blood and urine samples?
Page reference: Edexcel A2 Biology (concept) textbook

3. Steroid hormones
Pass through the plasma membrane and stimulate protein synthesis
Other steroid molecules
Steroid
hormones

4. Mechanism of action of steroid hormones:
cell surface membrane
Hormone enters cell and binds with receptor
Complex binds to DNA and acts as a
transcription factor
receptor
enters nucleus
nuclear
membrane
hormone-receptor
complex
Switches on a gene for synthesis of a protein

5. Testosterone Stimulates protein synthesis
Results in bigger and stronger muscles

6. Anabolic steroids
Natural testosterone is quickly broken down. Testosterone is modified to produce drugs that remain for longer in the body These synthetic anabolic steroids are illegal.
testosterone
nandrolone

7. Side-effects of using anabolic steroids
Infertility due to disruption of normal hormone production:
- disrupted menstrual cycle
- reduced sperm production
impotence In addition: - liver damage
- high blood pressure
- heart attacks
- increased aggression
21 year old body builder: A and B Severe acne conglobata C After 8 weeks off steroids and with antibiotics

8. Peptide hormones Peptide hormones do not enter the cell.
They bind to receptors on the cell surface membrane. They also act to switch genes on or off.
Human erythropoietin

9. Mechanism of action of peptide hormones:
receptor
cell surface membrane
Secondary messenger activated: initiates a protein kinase cascade
acts as a transcription factor which switches on gene for a specific protein
Inactive secondary messenger eg. cAMP
enters nucleus

10. Erythropoietin Erythropoietin is synthesised in the kidneys
Causes the synthesis of enzymes required for synthesis of red blood cells (erythrocytes) in bone marrow. Useful for treating anaemia.

11. Use of erythropoeitin
Increases number of blood cells and therefore enhances oxygen supply to muscles.
Improvement of 10% in aerobic performance
Use is popular with endurance athletes and cyclists

12. Side-effects of overuse of erythropoietin
Excess of red blood cells can lead to strokes and heart attacks .
Attacks most common at night due to low heart rate.
Thought to have caused the unexpected deaths of 18 european cyclists between
Abuse difficult to prove as it is naturally occurring.

13. Ethics of performance-enhancing drugs
Problems with deciding on what is illegal:
Ethical questions:
Creatine is not banned:
Classed as a nutritional supplement
Can cause kidney damage and high blood pressure
Is everything acceptable in the pursuit of sporting excellence?
Erythropoietin is banned:
Is a naturally occurring hormone
Can cause strokes and heart attacks
Isn´t it the choice of the athlete to risk using drugs or not?
Blood doping banned:
Donating, storing and transfusing own blood before
competition
Do use of performance- enhancing drugs improve or ruin competition?
High altitude training not banned:
Increases number of red blood cells.
Caused by natural increase in erythropoietin production.
Are there circumstances when drug use is acceptable?

14. Essay
Read pages 182 – 183 (of concept approach textbook) and answer question 2 on page 183:
Describe an absolutist and a relativist ethical position on the proposal to set a maximum total red blood cell count for athlete rather than measure erythropoietin levels.