This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Pituitary, Subject name: Physiology
Continuous administration of GnRH - 
Select and explain. 
A. Stimulates hypothalamic - pituitary axis, B. Suppresses hypothalamic - pituitary axis, C. May suppress or stimulatehypothalomic -pituitary axis, D. Has no effect on hypothalamic - pituitary axis
B: Suppresses hypothalamic - pituitary axis
Answer: B: Suppresses hypothalamic - pituitary axis 
Explanation: Ans. is 'b' i.e., Suppresses hypothalamic - pituitary axiso The timing and pattern of hypothalamic factor release are important determinants of anterior pituitary response,o Most hypothalamic releasing factors are secreted in a cyclic or pulsatile manner, rather than incontinuous manner.o For example, GnRH is normally secreted in episodic bursts, with a periodicity of few hours,o These bursts produce a circhoral peak of gonadotropins secretion, and these bursts are essential for normal secretion of gonadotropins.o If GnRH is administered by constant infusion, GnRH receptors in the anterior pituitary down-regulate and gonadotropins secretion is suppressed,