Ghrelin has been shown to suppress secretion of LH and, less regularly, of FSH in male and female animals and human males. However, no such evidence exists for human females.Objective:
The aim was to study the effect of ghrelin on secretion of LH and FSH in women.Design/Participants/Intervention:
Nocturnal (2000–0700 h) secretion profiles of LH and FSH were determined in six healthy women (age, 25.5 ± 2.9 yr) twice, receiving 50 μg ghrelin or placebo at 2200, 2300, 2400, and 0100 h in this single-blind, randomized, crossover study.Results:
LH secretion after ghrelin injection as assessed by the area under the curve (4.01 ± 1.37 mIU/min · ml) was significantly (P = 0.031) lower than after placebo injection (5.46 ± 1.33 mIU/min · ml). Also, FSH secretion after ghrelin injection (5.54 ± 0.64 mIU/min · ml) was significantly (P = 0.038) lower than after placebo injection (5.87 ± 0.56 mIU/min · ml). LH pulses occurred significantly (P = 0.007) less frequently after ghrelin injection (2.3 ± 0.5) than after placebo injection (3.8 ± 0.9). Accordingly, the interval between first and second LH pulse after treatment was significantly (P = 0.002) longer after ghrelin injection (300 ± 86 min) than after placebo injection (187 ± 60 min). One of the six women exhibited clear FSH pulses, which overall paralleled LH pulses; two FSH and LH pulses occurred after ghrelin injection, but three occurred after placebo in this woman.Conclusions:
This is the first report that ghrelin suppresses the secretion of LH and FSH in women. These findings resemble those in male and female animals and in men.