Faraday M M, Rahman M A, Scheufele P M, Grunberg N E
Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA.
Pharmacol Biochem Behav. 1998 Nov;61(3):281-9. doi: 10.1016/s0091-3057(98)00094-x.
In rats, effects of nicotine administration on sensory gating as indexed by prepulse inhibition (PPI) of the acoustic startle reflex (ASR) are unclear. We have found that nicotine administration enhances ASR and PPI in Sprague-Dawley rats, but other investigators, using Long-Evans rats, have reported no effects or enhancement of PPI only. Numerous methodological differences exist among studies in addition to subject strain, however, making it unclear whether inconsistent behavioral responses are the result of different experimental procedures or indicate a true strain difference. To investigate the role of strain in nicotine's effects on ASR and PPI, 192 male and female Long-Evans rats were administered 12 mg/kg/day nicotine via osmotic minipump for 14 days using identical methodologies employed in studies with Sprague-Dawley subjects. Effects of grouped vs. individual housing on these responses also were examined. Nicotine administration impaired ASR and PPI in Long-Evans subjects. These effects occurred in female rats regardless of housing condition, and interacted with housing in male rats. Results indicate that sex and housing are important variables in nicotine's effects. Results suggest that subject strain may be an important variable in nicotine's effects on sensory gating, and that responses of Sprague-Dawley vs. Long-Evans rats may represent a true strain difference.
在大鼠中，尼古丁给药对以听觉惊吓反射（ASR）的前脉冲抑制（PPI）为指标的感觉门控的影响尚不清楚。我们发现，给Sprague-Dawley大鼠注射尼古丁可增强ASR和PPI，但其他研究人员使用Long-Evans大鼠进行研究时，报告称没有影响，或者仅发现PPI增强。然而，除了实验对象的品系外，各项研究之间还存在许多方法学上的差异，这使得我们不清楚行为反应不一致是不同实验程序的结果，还是表明存在真正的品系差异。为了研究品系在尼古丁对ASR和PPI影响中的作用，我们采用与Sprague-Dawley实验对象研究相同的方法，通过渗透微型泵给192只雄性和雌性Long-Evans大鼠注射12 mg/kg/天的尼古丁，持续14天。我们还研究了群居与单独饲养对这些反应的影响。给Long-Evans实验对象注射尼古丁会损害ASR和PPI。这些影响在雌性大鼠中不受饲养条件的影响，但在雄性大鼠中与饲养条件相互作用。结果表明，性别和饲养条件是尼古丁作用的重要变量。结果还表明，实验对象的品系可能是尼古丁对感觉门控作用的一个重要变量，Sprague-Dawley大鼠和Long-Evans大鼠的反应可能代表了真正的品系差异。
