[lee-usmle]

If drug X was found to act like inhibin and drug Y was found to be drug X antagonist. Then administering drug Y could result in which of the following?
A- Male infertility
B- Increased Leydig cell testosterone synthesis
C- Decreased secretion of inhibin from granulosa cells
D- Increased FSH secretion from the anterior pituitary
E- Increased GnRH secretion from the hypothalamus

 

[jackat1000]

Sertoli cell inhibin produces negative feedback for FSH by the anterior pituitary gonadotrophs...so without Inhibin, FSH secretion production goes wild. Answer is D

 

[smile135]

antagonistic action of drug Y on drug x -------making normal action of drug x ( ie negative feedback inhibition on FSH secretion ) lost ......leading to increased FSH secretion from the ant pituitary

I choose D ?

 

[ahassan]

D i think is the correct answer

 

[HouseWannabe]

I completely agree with everyone that the answer is D be cause of the loss of the negative feedback on FSH, but i can't help but wonder if there is a loss of that negative feedback, wouldn't it be like having a sertoli cell tumor? Then we would see male infertility???

 

[lee-usmle]

Correct answer

Yes, the correct answer is D.
Inhibin has so far been of diagnostic significance in male infertility and it's anatagonist theoritcally may cause infertility but there's no such drug yet and it's not proven so you go with the more logical answer which is D.