Exam 1 - Performance Enhancing Drugs Flashcards
The effects of anabolic steroids are generally characterized by —-, while the effects of androgenic steroids are characterized by ——.
anabolic - strength and endurance
androgenic - masculinization (libido, acne, facial hair, growth of prostate, and deepening of voice)
Describe the setup and results of the exogenous testosterone muscle size/strength study.
4 groups - placebo and testosterone for both an exercise and no exercise group
testosterone increases muscle area and strength with or without exercise
combination of both testosterone and exercise gives greatest increase in muscle area and strength
People taking a higher dose of exogenous testosterone will have —– sperm concentrations.
lower
What is the basic steroid molecular structure?
A B C and D rings, with all being 6 carbon except for D, which is a 5 carbon ring
Carbons numbered 1-17, with 17 at the top of the D ring
Describe the structure and groups of a testosterone molecule
testosterone has A B C and D rings
Carbons 18 and 19 are methyl groups off of carbon 10 and 13
There is an OH and H on carbon 17
There is a =O on carbon 3
There is a double bond between carbon 4 and 5 of ring A
What kinds of structural modifications to testosterone can be used for synthetic steroids?
modify A and B rings to maximize anabolic activity and minimize androgenic activity
modify 17 carbon to determine oral or depot delivery
- 17 a-alkyl group confers oral activity by preventing deactivation by the gut or liver (first pass metabolism)
- esterification of 17 carbon confers activity for depot delivery (because it takes time for the ester group to be cleaved off and make the active form)
What are some routes of steroid drug administration?
oral (subject to first pass effect)
injection (subcutaneous or intramuscular)
pellet implant
transdermal (gel or patch)
sublingual troche
nasal spray
intra-vaginal
suppositories
What is the first pass effect/first pass metabolism?
drug metabolism where the concentration of the drug is greatly reduced before it reaches the systemic circulation
What are the 4 potential systems involved in first-pass metabolism?
gut wall enzymes
gastrointestinal lumen enzymes
bacterial enzymes
hepatic enzymes
How is a oral drug carried through the digestive system (vessels), and where does the concentration decrease?
enters the stomach at 100%, gut wall/gastrointestinal lumen/bacterial enzymes reduce to 70% which enters the hepatic portal vein, carries to liver where hepatic enzymes reduce it to 15%, and the hepatic vein carries that 15% into the systemic circulation
What vessels enter and exit the liver?
hepatic portal vein enters the liver from the digestive tract
hepatic vein enters the systemic circulation from the liver
Non-oral routes of administration are good because they…
Avoid first-pass metabolism and allow drugs to be absorbed directly into the systemic circulation
What structural modification happens to the testosterone molecule when it is converted to DHT?
The double bond is broken and a hydrogen is added on instead (there is no double bond between carbon 4 and 5)
Does testosterone or DHT have a greater affinity for androgen receptors?
DHT
How is the structure of nandrolone different from testosterone? What effect does this cause?
No 19 carbon (methyl group) on carbon 10
Greater affinity for androgen receptors than testosterone (more anabolic response)