Effects of leptin administration on lactational infertility in food-restricted rats depend on milk delivery.
نویسندگان
چکیده
Leptin administration has been shown to prevent the disruptive effects of acute food deprivation on reproductive function in cycling females and lactating females. We examined the ability of intracerebroventricular leptin administration to ameliorate the effects of food restriction for the first 2 wk postpartum on length of lactational infertility. Leptin administration did not reduce the effects of food restriction on reproductive function at either time period (days 8-15 and 15-22 postpartum) or dose (1 and 10 microg/day) administered. Because of the sharp contrast between these results and the ability of leptin to offset the effects of acute food deprivation in lactating rats, the remaining studies investigated the possible causes of this difference. Both central and peripheral leptin administration eliminated food deprivation-induced prolongation of lactational infertility, suggesting that neither route of administration nor dose was a factor. However, we noticed that, whereas chronically food-restricted females continue to deliver milk to their young, acutely food-deprived females do not. To test the hypothesis that the continued energetic drain of milk production and delivery might prevent the ability of exogenous leptin administration to eliminate the effects of undernutrition, leptin was administered to food-restricted, lactating rats prevented from delivering milk. In this situation intracerebroventricular leptin treatment completely eliminated the effects of food restriction on lactational infertility, suggesting that leptin contributes to the maintenance of reproductive function via two pathways: direct binding in the central nervous system and through increasing the availability of oxidizable metabolic fuels.
منابع مشابه
Effect of acute food deprivation on lactational infertility in rats is reduced by leptin administration.
The goals of these experiments were to determine whether lactational anestrus would be prolonged by a 48-h fast at days 13 and 14 postpartum (pp) and, if so, to determine whether this effect could be reversed by treatment with the Ob protein leptin. We found that food deprivation on days 13 and 14 pp prolonged lactational infertility by 7 days and that the nutritional experience of both the dam...
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ورودعنوان ژورنال:
- American journal of physiology. Regulatory, integrative and comparative physiology
دوره 286 1 شماره
صفحات -
تاریخ انتشار 2004