Maternal Adrenalectomy Abrogates the Effect of Fetal Alcohol Exposure on the Interleukin-1β-Induced Febrile Response: Gender Differences

Abstract

Fetal alcohol exposure (FAE) has been shown to blunt the febrile component of the primary host-defense response to infection induced experimentally by systemic administration of interleukin (IL)-1β. Given that maternal adrenalectomy (ADX) can prevent various postnatal effects of FAE, the present experiments were designed to determine whether maternal ADX would prevent the blunted IL-1β-induced febrile response of fetal alcohol-exposed offspring and whether the effects of maternal ADX would be gender related. Timed-pregnant rats underwent ADX or were sham-operated on gestation day (GD) 7, or remained intact (without any surgery), and were fed ethanol-containing (E) or pair-fed (PF) liquid diets or normal (N) rat chow and water from GD 8 to GD 21. As adults, male and female E, PF and N offspring were injected with saline on day 1 and with IL-1β (2 µg/kg, i.p.) on day 2 at 09.00 h and the body temperature was recorded biotelemetrically for 8.5 h. IL-1β produced significantly lower febrile responses in female than in male offspring of intact dams, irrespective of prenatal diet. Furthermore, prenatal surgical stress differentially affected the IL-1β-induced febrile response of male and female normally fed offspring. Additionally, in both male and female offspring of intact dams, FAE significantly attenuated the IL-1β-induced febrile response. In males, FAE also attenuated the febrile response in the offspring of maternal sham-operated dams, and this effect was completely reversed by maternal ADX. In females, both maternal sham surgery and ADX reversed the effect of FAE on the febrile response. These findings suggest that maternal adrenal mediators are essential for the long-term effect of FAE on the febrile response in male offspring. In females, early prenatal surgical stress is sufficient to reverse the effects of FAE, possibly via adrenal-independent mechanisms that affect the thermoregulatory system.