Martin B J, Wehner J M
Department of Psychology, University of Colorado, Boulder 80309.
Pharmacol Biochem Behav. 1988 Aug;30(4):1065-70. doi: 10.1016/0091-3057(88)90140-2.
Acute exposure to nicotine produces an elevation of plasma corticosterone levels in rodents. The consequences of repeated exposure to nicotine administered intraperitoneally (IP) were examined in three inbred strains of mice, DBA/2Ibg, C3H/2Ibg and A/J. These strains of mice have been shown previously to differ in a variety of behavioral and physiological responses to acute nicotine exposure. Mice were administered saline or 1.00 mg/kg nicotine IP, followed 30 min later by a range of nicotine doses (0.25-1.00 mg/kg). Strain differences were observed for the dose-response to the second injection; however, no effect of acute nicotine pretreatment was demonstrated. The observed lack of desensitization was consistent across genotype. An intragastric administration of a pretreatment dose of nicotine (4.00 mg/kg) also failed to produce desensitization to a subsequent IP nicotine injection in any strain. Increasing the time interval between injections to 45 min did not alter the CCS response. However, at 90 min between injections, a supersensitive CCS response was measured in all strains.
急性接触尼古丁会使啮齿动物的血浆皮质酮水平升高。在三种近交系小鼠DBA/2Ibg、C3H/2Ibg和A/J中研究了腹腔注射（IP）尼古丁反复接触的后果。先前已表明，这些品系的小鼠对急性尼古丁接触的各种行为和生理反应存在差异。给小鼠腹腔注射生理盐水或1.00 mg/kg尼古丁，30分钟后再注射一系列尼古丁剂量（0.25 - 1.00 mg/kg）。观察到第二次注射的剂量反应存在品系差异；然而，未显示急性尼古丁预处理有任何作用。在不同基因型中均观察到缺乏脱敏现象。胃内给予预处理剂量的尼古丁（4.00 mg/kg）也未能使任何品系对随后的腹腔注射尼古丁产生脱敏作用。将注射间隔时间增加到45分钟并未改变条件性位置偏爱（CCS）反应。然而，在注射间隔90分钟时，所有品系均检测到超敏的CCS反应。
