Week 4: Reproductive Pharmacology: Androgens

Question 1

Testosterone MOA

Answer 1

• Acts via binding to androgen receptor which binds to androgen response elements in target genes: Regulates gene transcription

Question 2

Testosterone Clinical uses

Answer 2

• Primary clinical use is for replacement therapy for hypogonadism
• has also been used to stimulate red blood cell production in certain anemias and to promote weight gain in patients with wasting syndromes (eg AIDS patients)

Question 3

Testosterone side effects

Answer 3

Use of androgens by females results in virilization and menstrual irregularity

Question 4

Testosterone contraindications

Answer 4

• In women who are pregnant with a female fetus
  
  • exogenous androgens can cause virilization of the fetuses’ external genitalia
• High doses can cause feminization in males
• In both sexes:
  
  • high doses of anabolic steroids can cause cholestatic jaundice, elevation of liver enzyme levels
  • possibly hepatocellular carcinoma

Question 5

Testosterone notes

Answer 5

• In skin, prostate, seminal vesicles and epididymis testosterone is converted to 5α-dihydrotestosterone by 5α-reductase (in these tissues 5α-DHT is the dominant androgen)
• In the plasma, testosterone is partly bound to SHBG
• Plasma SHBG is increased by estrogen and decreased by testosterone