Conclusions
Acute intravenous infusion of 0.4 pmol/kg/min PYY does not affect the reproductive axis in healthy men.
Objective
To investigate the effects of PYY administration on the reproductive axis in healthy young men. Design: Single-blind, randomized, placebo-controlled crossover study. Setting: Clinical Research Facility, Imperial College Healthcare NHS Trust. Participants: Eighteen healthy eugonadal men (mean age 24.1 ± 0.9 years, mean body mass index 22.2 ± 0.4 kg/m2). Intervention: Eight-hour intravenous infusion of 0.4 pmol/kg/min PYY3-36 or rate-matched vehicle infusion. Main outcome measures: Number of luteinizing hormone (LH) pulses, LH, follicle stimulating hormone (FSH), and testosterone levels.
Results
The number of LH pulses (mean number of LH pulses/8 hours: PYY 4.4 ± 0.3 vs vehicle 4.4 ± 0.4, P > .99), LH area under the curve (AUC) (PYY 1503 ± 79 IU.min/L vs vehicle 1574 ± 86 IU.min/L, P = .36), FSH AUC (PYY 1158 ± 513 IU.min/L vs vehicle 1199 ± 476 IU.min/L, P = .49) and testosterone AUC (PYY 10 485 ± 684 IU.min/L vs vehicle 11 133 ± 803 IU.min/L, P = .24) were similar during PYY and vehicle infusions. Conclusions: Acute intravenous infusion of 0.4 pmol/kg/min PYY does not affect the reproductive axis in healthy men.