Milde Anne Marita, Enger Øystein, Murison Robert
Department of Biological and Medical Psychology, University of Bergen, Jonas Liesvei 91, 5009 Bergen, Norway.
Physiol Behav. 2004 Mar;81(1):71-84. doi: 10.1016/j.physbeh.2004.01.002.
In this study, we investigated the effects of three neonatal conditions on adult corticosterone (CORT) levels, acoustic startle responses (ASRs), and vulnerability to colitis induced by dextran sulfate sodium (DSS) and how these early manipulations might interact with a brief stress exposure in adulthood on the same measures. Infant animals were subjected daily to either 180-min maternal separation [prolonged maternal separation (LMS)], 10-min maternal separation [brief maternal separation (BMS)], or nonhandling (NH) conditions during postnatal days 1-14. As adults, half of the animals were exposed to a series of 10 uncontrollable foot shocks. Animals were tested for CORT levels prior to and 10 days following shock/nonshock procedures before being tested for ASRs. Finally, all animals were exposed to 4% DSS in their drinking water for 6 days. LMS animals showed enhanced vulnerability to DSS-induced colitis when previously exposed to shock and enhanced stress reactivity responses as shown by elevated startle and CORT levels. Among the nonshocked animals, NH animals showed most colonic damage. Taken together, the results support previous findings suggesting that BMS has a protective effect on adult stress exposure. Additionally, BMS protects the animals from chemically induced colitis. The NH condition has clearly an effect on sensitizing mucosal response to DSS exposure.
在本研究中，我们调查了三种新生期状况对成年动物皮质酮（CORT）水平、听觉惊吓反应（ASR）以及对葡聚糖硫酸钠（DSS）诱导的结肠炎易感性的影响，以及这些早期处理如何在相同指标上与成年期的短暂应激暴露相互作用。在出生后第1 - 14天，每天对幼龄动物进行180分钟的母婴分离[长时间母婴分离（LMS）]、10分钟的母婴分离[短暂母婴分离（BMS）]或不处理（NH）。成年后，一半的动物接受一系列10次不可控的足部电击。在电击/非电击程序之前和之后10天对动物进行CORT水平测试，然后进行ASR测试。最后，所有动物饮用含4% DSS的水6天。LMS动物在先前遭受电击时对DSS诱导的结肠炎表现出更高的易感性，并且如惊吓和CORT水平升高所示，应激反应性增强。在未受电击的动物中，NH动物的结肠损伤最为严重。综上所述，结果支持先前的研究结果，即BMS对成年期应激暴露具有保护作用。此外，BMS可保护动物免受化学诱导的结肠炎。NH状况显然对使黏膜对DSS暴露敏感化有影响。
