Page 15 - FLIPBOOK

Mechanisms of Action: LHRH Agonists and

Antagonists

LHRH agonists
Negative feedback control Testosterone (95%)
• Overstimulate the pituitary gland Testes
and over-ride the pulsatile control

of LH release by natural LHRH
Pulsatile release LH
• Result: downregulation of LHRH of GnRH every

receptors and desensitization of 90-120 mins
the gland

LHRH antagonists
Hypothalamus Pituitary ACTH
• Directly bind to the pituitary

• Prevent release of LH + FSH Prostate

• Result: Removes stimulus to the Adrenal glands
testes to produce T Negative feedback control Adrenal androgens (5%)

ACTH Adrenocorticotropic hormone FSH Follicle-stimulating hormone
GnRH Gonadotropin-releasing hormone LH Luteinizing hormone T Testosterone Drudge-Coates L. Int J Urological Nursing 2010;3:85-92