Ghrelin Suppresses Secretion of Luteinizing Hormone (LH) and Follicle-Stimulating Hormone (FSH) in Women

Abstract

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. 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. 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. 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.