Pituitary function in adult males receiving medroxyprogesterone acetate

Area of Science:

• Endocrinology
• Neuroendocrinology
• Behavioral Science

Background:

• Medroxyprogesterone acetate (MPA) is used to treat antisocial and sex-offending behaviors.
• The effects of MPA on pituitary, adrenal, and gonadal functions require further investigation.

Purpose of the Study:

• To evaluate the impact of MPA therapy on pituitary, adrenal, and gonadal functions in males with behavioral issues.
• To assess changes in hormone levels, including gonadotropins, testosterone, growth hormone, and cortisol.

Main Methods:

• Nine males (six XY, two XYY, one XY/XYY) receiving MPA therapy for at least 6 months were studied.
• Hormone levels (gonadotropins, testosterone, growth hormone, cortisol) were measured before and during MPA therapy.
• Analysis included 24-hour rhythms, integrated concentrations, and responses to insulin-induced hypoglycemia.

Main Results:

• MPA therapy significantly decreased serum gonadotropin and plasma testosterone concentrations.
• No changes were observed in the 24-hour rhythm or integrated concentration of growth hormone.
• The plasma cortisol circadian rhythm was suppressed, and 24-hour integrated cortisol concentrations decreased significantly (P < 0.001), but the cortisol response to hypoglycemia remained unchanged.

Conclusions:

• MPA therapy impacts the hypothalamic-pituitary-gonadal axis by reducing gonadotropin and testosterone levels.
• MPA affects the hypothalamic-pituitary-adrenal axis, suppressing cortisol circadian rhythm and overall concentration, but preserves the stress response.
• MPA does not influence growth hormone secretion patterns.