Leuprorelin acetate is a synthetic gonadotropin-releasing hormone (GnRH) analogue that plays an important role in modern endocrine therapy and cancer treatment. It inhibits sex hormone secretion by regulating the function of the hypothalamus-pituitary-gonadal axis (HPG axis).
Pharmacological Mechanism
Under normal physiological conditions, GnRH is secreted by the hypothalamus in a pulsatile manner, stimulating the pituitary gland to release luteinizing hormone (LH) and follicle-stimulating hormone (FSH), thereby regulating the secretion of estrogen or androgen by the gonads.
Leuprorelin acetate exhibits a "activation followed by inhibition" characteristic:
Initial stimulation phase: In the initial stage of use, it temporarily increases LH and FSH secretion, leading to an increase in sex hormone levels (known as the "flare effect").
Continuous use phase: Due to continuous stimulation of GnRH receptors, the receptors undergo desensitization and downregulation, ultimately inhibiting LH and FSH secretion.
Final effect: Significantly reduces estrogen or testosterone levels in the body, achieving a "chemical castration" effect.
