Lewis Michael C, Gould Thomas J
Department of Psychology, Weiss Hall, Temple University, 1701 N 13th Street, Philadelphia, PA 19122, USA.
Pharmacol Biochem Behav. 2003 Aug;76(1):179-86. doi: 10.1016/s0091-3057(03)00213-2.
Nicotine has been shown to have additive as well as antagonistic effects on behavior stimulated by ethanol. Here, we examine the effects of nicotine, ethanol, and the coadministration of each drug on acoustic startle responding in C57BL/6J mice. Mice were tested at a range of decibel levels (80-115 dB, 5 dB increments), with administration of 0.031, 0.062, 0.125, and 0.25 mg/kg nicotine or 0.5, 1.0, 1.5, and 2.0 g/kg ethanol. Nicotine and ethanol each caused an increase in the acoustic startle response at the highest and lowest doses tested, respectively. Mecamylamine, a nicotinic receptor antagonist, administered in combination with nicotine or ethanol attenuated these increases in acoustic startle responding. Nicotine and ethanol, administered together, did not produce greater enhancement of startle than when administered alone. Haloperidol (1 mg/kg) was administered in combination with nicotine or ethanol to investigate if dopamine modulated nicotine or ethanol enhancement of acoustic startle. It was found that the increase in acoustic startle responses observed with ethanol or nicotine was attenuated by haloperidol. Thus, ethanol or nicotine may enhance the acoustic startle reflex through a common dopaminergic mechanism.
已证明尼古丁对乙醇刺激的行为具有相加和拮抗作用。在此，我们研究尼古丁、乙醇以及每种药物联合给药对C57BL/6J小鼠听觉惊吓反应的影响。小鼠在一系列分贝水平（80 - 115分贝，以5分贝递增）下进行测试，分别给予0.031、0.062、0.125和0.25毫克/千克尼古丁或0.5、1.0、1.5和2.0克/千克乙醇。尼古丁和乙醇分别在测试的最高和最低剂量下均引起听觉惊吓反应增加。烟碱受体拮抗剂美加明与尼古丁或乙醇联合给药可减弱听觉惊吓反应的这些增加。尼古丁和乙醇一起给药时，对惊吓反应的增强作用并不比单独给药时更大。给予氟哌啶醇（1毫克/千克）与尼古丁或乙醇联合使用，以研究多巴胺是否调节尼古丁或乙醇对听觉惊吓的增强作用。结果发现，氟哌啶醇减弱了乙醇或尼古丁引起的听觉惊吓反应增加。因此，乙醇或尼古丁可能通过共同的多巴胺能机制增强听觉惊吓反射。
