Acute Re-Feeding Reverses Food Restriction-Induced Hypothalamic-Pituitary-Gonadal Axis Deficits1

Abstract

Undernutrition has well-established effects on female reproduction. Here we describe the effects of food restriction on aspects of the hypothalamic-pituitary-gonadal (HPG) axis in the female musk shrew. We determined that acute re-feeding reverses deficits brought on by food restriction. Two days of food restriction led to an increase in proGnRH immunoreactive cells in the preoptic area relative to ad libitum-fed controls (AL). This increase was reversed by 90 min of ad libitum feeding in the re-fed females (RF). In addition, food-restricted (FR) females had significantly greater GnRH content in the median eminence than either the AL or RF females. After GnRH was administered, the majority of females in all food conditions ovulated, yet the FR females had significantly fewer corpora lutea than either the AL or RF animals. These data show that food restriction impairs HPG axis function in female musk shrews, and that some of these impairments can be rapidly reversed by acute re-feeding.