Hashimoto M, Watanabe T, Fujioka T, Tan N, Yamashita H, Nakamura S
Department of Physiology, Yamaguchi University School of Medicine, 1-1-1 Minami-Kogushi, Ube, Yamaguchi 755-8505, Japan.
Physiol Behav. 2001 May;73(1-2):125-32. doi: 10.1016/s0031-9384(01)00473-5.
The present study was carried out to investigate the effects of prenatal stress on stress-induced hyperthermia in adult rats. Prenatal stress was administered daily for 3 days (embryonic days 15-17) by restraining pregnant rats in a small cage either for 30 or 240 min. After birth, foster mothers raised the pups. Offspring were tested at 9-10-weeks-old. Changes in body temperature and in the plasma concentrations of corticosterone, norepinephrine (NE), and epinephrine (Epi) induced by restraint or lipopolysaccharide (LPS)-induced stress were examined. By comparison with the prenatally nonstressed control group, the 240-min stress group showed a significantly lower hyperthermia in response to restraint stress but a higher fever after injection of LPS. The 30-min stress group showed similar alterations in these hyperthermic responses but did not reach significance. Both the restraint stress and the injection of LPS evoked greater increases in the plasma level of corticosterone in the 240-min stress group than in the control group. Although restraint stress induced significant increases in NE and Epi in the control and 30-min stress groups, the plasma levels of these catecholamines did not increase in the 240-min stress group. These results demonstrate for the first time that prenatal stress has opposite effects on the hyperthermic responses to restraint and LPS injection, suggesting that different mechanisms underlie the modulating effects of prenatal stress on the responses to the two types of stressors.
本研究旨在探讨产前应激对成年大鼠应激诱导的体温过高的影响。在胚胎期第15至17天，通过将怀孕大鼠置于小笼中束缚30或240分钟，每日施加一次产前应激，持续3天。出生后，由代孕母鼠抚养幼崽。在幼崽9至10周龄时进行测试。检测了束缚或脂多糖（LPS）诱导的应激所引起的体温、血浆皮质酮、去甲肾上腺素（NE）和肾上腺素（Epi）浓度的变化。与产前未应激的对照组相比，240分钟应激组对束缚应激的体温过高反应显著降低，但注射LPS后发热更高。30分钟应激组在这些体温过高反应中表现出类似变化，但未达到显著水平。与对照组相比，束缚应激和注射LPS均使240分钟应激组血浆皮质酮水平升高幅度更大。虽然束缚应激在对照组和30分钟应激组中均诱导NE和Epi显著增加，但在240分钟应激组中，这些儿茶酚胺的血浆水平并未升高。这些结果首次证明，产前应激对束缚和LPS注射引起的体温过高反应具有相反作用，表明产前应激对两种应激源反应的调节作用存在不同机制。
