drugs in sport

Question 1

what does angiotensin II do?

Answer 1

increases blood pressure by stimulating Gq -> IP3 -> higher [Ca2+] -> contraction

Question 2

what is the effect of ACE deletions on exercise?

Answer 2

• higher levels of ACE
• increased angiotensin II
• increase in factors for muscle growth
• muscle hypertrophy

Question 3

what type of athletes are ACE deletions found in?

Answer 3

short distance swimmers

Question 4

what is the effect of ACE insertions on exercise?

Answer 4

• lower levels of ACE
• decrease in angiotensin II
• increase in bradykinin (vasodilator)
• improved vasodilation and substrate metabolism

Question 5

what type of athletes are ACE deletions found in?

Answer 5

elite distance runners, rowers, cyclists

Question 6

what are the cellular responses to IGF-1?

Answer 6

• activation of Akt +mTOR -> protein synthesis, growth, proliferation, metabolism and survival
• activation of ERK (MAPK) -> proliferation

Question 7

how does exercise promote protein synthesis and hypertrophy?

Answer 7

environmental and circulating stimuli cause pituitary to secrete growth hormone, which causes the liver to secrete IGF-1, which promotes tissue growth and remodelling

Question 8

what are IGF-1 polymorphisms associated with?

Answer 8

studies have shown IGF-1 polymorphisms to be associated with responses to strength training in the elderly

Question 9

what is the impact of exercise on genes and transcription?

Answer 9

stimulates genes expression changes underlying structural and metabolic adaptations. this can be via alterations in gene silencing via DNA methylation, histone modification and RNA associated silencing

Question 10

what is PGC-1a?

Answer 10

peroxisome proliferator activated receptor gamma coactivator 1. regulates genes involved with energy metabolism, mitochondrial biogenesis and function

Question 11

how is VO2max affected by genetic variations?

Answer 11

genetic variations account for 40% of variation in VO2max with aerobic training

Question 12

what was the heritage family study?

Answer 12

a multi-centre study on the role of genotype in cardiovascular and metabolic responses to aerobic exercise and changes to risk factors for several cardiovascular diseases and diabetes by aerobic exercise

Question 13

what were the findings of the heritage study?

Answer 13

aerobic endurance training over 20 weeks caused

• average increase in VO2max of 19%
• greater variability in VO2max between families than within them
• there is a genetic component to VO2max and an association with muscle creatine kinase

Question 14

from which endocrine glands/organs are androgens produced?

Answer 14

• adrenal glands
• ovaries
• testes

Question 15

what type of androgens are secreted from the adrenal glands and ovaries?

Answer 15

weak androgens, these must undergo peripheral conversion to testosterone

Question 16

what is the difference between testosterone and 5a-dihydrotestosterone?

Answer 16

5a-dihydrotestosterone is produced via peripheral conversion and has higher affinity for the androgen receptor

Question 17

in which three forms is testosterone found in the blood stream?

Answer 17

• strongly found bound to sex hormone binding globulin (70%)
• found bound weakly to albumin (30%)
• unbound (0.5-0.3%)

Question 18

what are the sub-families of steroid hormone receptor?

Answer 18

3A - estrogen receptor

3C- androgen receptor, progesterone receptor, glucocorticoid receptor

Question 19

Where is androgen receptor found?

Answer 19

in the cytoplasm, bound to other proteins which stabilise their position

Question 20

what is the effect of ligand binding to androgen receptor?

Answer 20

change in conformation, reducing affinity for chaperone proteins, allowing androgen receptor to act. the androgen receptor moves into the nucleus, dimerising to allow assembly of a large transcriptional compplex

Question 21

what are the two types of effect of anabolic steroids?

Answer 21

androgenic effects

anabolic effects

Question 22

how are steroids modified to improve their effects?

Answer 22

changes to hydroxyl group can change bioavailability

changes to cyclohexane rings can increase anabolic effects

Question 23

what is the goal of making changes to anabolic steroids?

Answer 23

• slow inactivation
• reduce hepatic degradation
• increase lipid solubility
• increase anabolic:androgenic ratio

Question 24

what morphometric changes occur upon the use of anabolic steroids?

Answer 24

• increased muscle volume
• increased cross-sectional area of type I and II fibres
• no difference in fibre proportions
• hyperplasia
• increased lean mass
• increased myonuclear number

Question 25

what are morphometric changes caused by anabolic steroids associated with?

Answer 25

• increased protein synthesis
• reduced amino acid export
• increased androgen receptor expression
• fibre hypertrophy causing an increase in strength
• increase in calcium release and sensitivity of contractile proteins to calcium

Question 26

increased muscle pinnation can be caused by anabolic steroid use, what is this?

Answer 26

when fascicles are attached to the tendon in a slanting position, allows higher force but smaller range of movement

Question 27

what did measurements following intramuscular injection of nandrolone decanoate?

Answer 27

• decreased serum creatinine
• increase in strength
• decreased mitotic activity of satellite cells
• increased leucine uptake, increase in protein synthesis

Question 28

what are the functional effects of intramuscular nandrolone decanoate injection?

Answer 28

• decreased damage to muscle
• increased capacity to do work
• higher fatigue resistance
• increased collagen synthesis
• increased bone mineral density

Question 29

what are the complimentary effects of anabolic steroids?

Answer 29

• antagonism of catabolic effects of glucocorticoids
• stimulation of growth hormone insulin-like growth factor
• psychoactive effects: mood elevation, aggressiveness

Question 30

what are the side effects of anabolic steroids?

Answer 30

• cardiovascular disease (impaired diastolic filling, dilated cardiomyopathy, increased left ventricular mass, arrhythmias)
• liver dysfunction
• cancer

Question 31

what are the desired effects of stimulants?

Answer 31

• increased alertness, self-confidence, concentration, reduction in fatigue
• increased speed, power, endurance, and concentration

Question 32

what types of stimulants are there?

Answer 32

• sympathomimetic amines
• CNS stimulants
• psychomotor stimulants

Question 33

what effects of stimulants make their use in sport unfair?

Answer 33

increased cardiac output, increased blood flow to muscles, locomotor stimulation

Question 34

what is amphetamine?

Answer 34

an indirectly acting sympathomimetic stimulant that is structurally related to monoamine neurotransmitters adrenaline and noradrenaline

Question 35

why are amphetamines orally active?

Answer 35

they are resistant to MAO (monoamine oxidase)

Question 36

what is the mechanism of action for amphetamines?

Answer 36

• substrates for the neuronal plasma membrane monoamine uptake transporters DAT and NET, acting as competitive inhibitors
• enter nerve terminals and interact with vesicular monoamine pump VMAT2 to inhibit uptake into synaptic vesicles of cytoplasmic dopamine and noradrenaline
• concentration of extracellular dopamine and noradrenaline in the vicinity of the synapse increases

Question 37

what are the acute side effects of amphetamine use?

Answer 37

• increased HR, bp, restlessness, insomnia, agitation, GI upset, nausea, headache, convulsions, hallucinations, paranoia
• distortion of reality
• death due to ruptured blood vessels in the brain, heart attack due to abnormal heart rthythms

Question 38

what are the chronic side effects of amphetamine use?

Answer 38

• dyskinesias
• compulsive and repetitive behaviour
• paranoia

Question 39

what are the clinical uses for amphetamine?

Answer 39

• ocular actions: pupil dilation, reduction of intraocular pressure
• nasal decongestants
• narcolepsy
• ADHD