Felszeghy K, Sasvári M, Nyakas C
Department of Clinical and Experimental Laboratory Investigations, Postgraduate Medical School, Budapest, Hungary.
Horm Behav. 1993 Sep;27(3):380-96. doi: 10.1006/hbeh.1993.1028.
Permanent changes in novelty-induced arousal and behavioral depression were studied in adult male Wistar rats having received sc injections of 1 micrograms/g body wt dexamethasone (DEX) or ACTH-(4-9) analogue (ORG 2766), or the combined treatment of these substances at Postnatal Days 1, 3, and 5. Treatment with DEX increased immobility in the Porsolt's water immersion and closed-field tests, delayed start latency, and attenuated orientation motility in an open-field, and enhanced defensive burying activity. On the contrary, the ACTH peptide caused more active behavior, resulted in an increased motility in the Porsolt's test, and decreased immobility in the closed-field chamber compared to controls. Behavioral reactivity of rats after combined DEX and ACTH peptide treatments was comparable to that of saline controls. The hormone treatments did not alter basal and stress-induced circulating corticosterone levels assessed at the adult age. The data suggest that neonatal DEX strengthens the development of brain mechanisms supporting behavioral depression in response to stressful situations, while ORG 2766 has principally an opposite effect and is able to compensate the long-term aberrant behavioral effects of neonatal DEX treatment.
研究了成年雄性Wistar大鼠在出生后第1、3和5天接受皮下注射1微克/克体重的地塞米松（DEX）或促肾上腺皮质激素（ACTH）-(4 - 9)类似物（ORG 2766），或这两种物质联合治疗后，新奇诱导的唤醒和行为抑郁的永久性变化。DEX治疗增加了波索尔特水浸试验和封闭场试验中的不动时间，延迟了起始潜伏期，减弱了旷场试验中的定向运动，并增强了防御性埋埋活动。相反，与对照组相比，ACTH肽导致更活跃的行为，在波索尔特试验中增加了运动能力，并减少了封闭场室中的不动时间。DEX和ACTH肽联合治疗后大鼠的行为反应性与生理盐水对照组相当。激素治疗并未改变成年时评估的基础和应激诱导的循环皮质酮水平。数据表明，新生期DEX增强了支持对应激情况产生行为抑郁的脑机制的发育，而ORG 2766主要具有相反的作用，能够补偿新生期DEX治疗的长期异常行为影响。
