Hijzen T H, Broersen L M, Slangen J L
Department of Psychopharmacology, University of Utrecht, The Netherlands.
Biol Psychiatry. 1991 Jun 1;29(11):1119-28. doi: 10.1016/0006-3223(91)90254-j.
Prepulse inhibition of the startle reflex has been used as an animal model for information processing deficits found in some types of schizophrenia. These deficits may be mediated by hypersensitive dopaminergic systems. In the present study, the effects of subchronic d-amphetamine administration [2 mg/kg intraperitoneally (IP)] on prepulse and gap inhibition of the startle reflex were compared to the effects of acute amphetamine and saline administration on startle inhibition. Results of three experiments are reported. The first two experiments were used to select prestimulus parameters sensitive to changes in stimulus intensity on the one hand, and prestimulus parameters sensitive to temporal aspects of stimulus processing on the other hand. Because schizophrenics have problems with the temporal sequencing of information, prestimulus inhibition of the startle reflex was expected to be more pronounced when prestimulus processing depended predominantly upon temporal factors. Results supported this hypothesis, although the effects of d-amphetamine were found at near detection threshold duration only. Subchronic amphetamine had no effect on the neuronal mechanisms underlying inhibition of the startle reflex by prestimuli. The results also suggested that a careful selection of duration and intensity of the prestimulus may increase the sensitivity of the prestimulus-startle paradigm for the effects of drugs, for example.
惊吓反射的前脉冲抑制已被用作一种动物模型，用于研究某些类型精神分裂症中发现的信息处理缺陷。这些缺陷可能由超敏多巴胺能系统介导。在本研究中，将亚慢性给予d-苯丙胺[2mg/kg腹腔注射（IP）]对惊吓反射的前脉冲和间隔抑制的影响，与急性给予苯丙胺和生理盐水对惊吓抑制的影响进行了比较。报告了三个实验的结果。前两个实验一方面用于选择对刺激强度变化敏感的刺激前参数，另一方面用于选择对刺激处理的时间方面敏感的刺激前参数。由于精神分裂症患者在信息的时间序列方面存在问题，当刺激前处理主要依赖于时间因素时，预计惊吓反射的刺激前抑制会更明显。结果支持了这一假设，尽管仅在接近检测阈值持续时间时发现了d-苯丙胺的作用。亚慢性苯丙胺对刺激前抑制惊吓反射的神经元机制没有影响。结果还表明，例如，仔细选择刺激前的持续时间和强度可能会提高刺激前-惊吓范式对药物作用的敏感性。
