Maslova Larissa N, Bulygina Veta V, Popova Nina K
Institute of Cytology and Genetics, Siberian Branch of Russian Academy of Sciences, Novosibirsk 630090, Russia.
Physiol Behav. 2002;75(1-2):217-25. doi: 10.1016/s0031-9384(01)00648-5.
The immediate and long-lasting effects of two models of chronic stress during the prepubertal period of life (21-32 days) on the acoustic startle response (ASR) were studied in outbred Wistar normotensives and rats with inherited stress-induced arterial hypertension (ISIAH) derived from them. Chronic variable stress (CVS) and repeated handling were used as chronic treatment. The obtained data showed a significantly attenuated ASR and a greater magnitude of prepulse inhibition (PPI) in juvenile and adult ISIAH compared to Wistar rats. The immediate effects of prolonged stress on the ASR were genotype-dependent. Young ISIAH rats exposed to both types of prepubertal stimulation had higher ASR than the age-matched controls. No significant stress-induced changes in the ASR were found in young Wistar rats. The long-lasting consequences of prolonged prepubertal stress were similar in the two strains and were determined by the specificity of stress stimulation: chronic handling had no effect on the ASR, while CVS enhanced it. The long-lasting effect of CVS experienced in prepubertal life appears to produce ASR changes similar to those seen in patients with posttraumatic stress disorder (PTSD). The magnitude of PPI increased from early age to adulthood and it was tolerant to environmental influences. The two rat strains did not differ in the rate of short-term habituation to repeated acoustic stimuli, which was unaffected by prepubertal stress. Evidence was obtained indicating that genetic and environmental background in childhood may contribute to the truncation of the startle response.
在断奶前时期（21 - 32天），对远交系Wistar正常血压大鼠以及由其衍生的遗传性应激诱导型动脉高血压（ISIAH）大鼠，研究了两种慢性应激模型对听觉惊吓反应（ASR）的即时和长期影响。采用慢性可变应激（CVS）和反复处理作为慢性处理方式。所得数据显示，与Wistar大鼠相比，幼年和成年ISIAH大鼠的ASR显著减弱，前脉冲抑制（PPI）幅度更大。长期应激对ASR的即时影响具有基因型依赖性。暴露于两种断奶前刺激类型的幼年ISIAH大鼠的ASR高于年龄匹配的对照组。在幼年Wistar大鼠中未发现应激诱导的ASR有显著变化。断奶前长期应激的长期后果在两个品系中相似，且由应激刺激的特异性决定：反复处理对ASR无影响，而CVS增强了ASR。断奶前经历的CVS的长期影响似乎产生了与创伤后应激障碍（PTSD）患者相似的ASR变化。PPI的幅度从幼年到成年期增加，且不受环境影响。两种大鼠品系对反复听觉刺激的短期习惯化速率没有差异，这不受断奶前应激的影响。有证据表明，儿童期的遗传和环境背景可能导致惊吓反应的减弱。
