Clarke P B, Kumar R
Br J Pharmacol. 1984 May;82(1):233-9. doi: 10.1111/j.1476-5381.1984.tb16463.x.
Undeprived rats were tested in their home cages for intake of water and powered food, starting 15 min after subcutaneous (s.c.) injection of (-)-nicotine bitartrate or 0.9% w/v NaCl solution (saline). In the first 2 h, nicotine (0-0.4 mg kg-1 base) markedly reduced water intake in a dose-related way, leaving food intake unchanged. Food and water intake up to 24 h after injection was unaffected. Rats (n = 6 per group) were then injected daily with nicotine (0.4 mg kg-1 base, s.c.) or saline for one month. Intermittent tests with saline (in place of nicotine) during this period did not reveal any signs of abstinence. A dose-response study similar to the first was then carried out, and little or no tolerance was found to the hypodipsic action of nicotine. Nicotine also reduced food intake, irrespective of chronic treatment. Subsequently, daily injections were discontinued, and spontaneous intake did not differ in rats previously maintained on nicotine, relative to control animals. Mecamylamine (0.3, 1.5 mg kg-1, s.c.) prevented nicotine-induced hypodipsia, whereas chlorisondamine (0.02, 0.1 mg kg-1 s.c.) was ineffective. Both ganglion blockers reduced food intake. Nicotine did not reduce drinking in rats preloaded with a hypertonic saline solution. It is suggested that nicotine reduces water intake in undeprived rats, probably by acting centrally. Since this action changes little with repeated testing, it may provide a useful index of one or more central actions of the drug.
未被剥夺食物和水的大鼠在其饲养笼中接受水和粉状食物摄入量的测试，在皮下注射（s.c.）（-）-酒石酸尼古丁或0.9% w/v氯化钠溶液（生理盐水）15分钟后开始。在最初的2小时内，尼古丁（0 - 0.4毫克/千克碱）以剂量相关的方式显著减少水的摄入量，而食物摄入量不变。注射后长达24小时的食物和水摄入量未受影响。然后，大鼠（每组n = 6）每天皮下注射尼古丁（0.4毫克/千克碱）或生理盐水，持续一个月。在此期间用生理盐水（代替尼古丁）进行的间歇性测试未发现任何戒断迹象。然后进行了一项与第一次类似的剂量反应研究，发现对尼古丁的低饮水作用几乎没有耐受性。无论长期治疗如何，尼古丁也会减少食物摄入量。随后，停止每日注射，相对于对照动物，先前用尼古丁维持的大鼠的自发摄入量没有差异。美加明（0.3、1.5毫克/千克，皮下注射）可预防尼古丁引起的低饮水，而氯异吲哚胺（0.02、0.1毫克/千克，皮下注射）无效。两种神经节阻滞剂均会减少食物摄入量。尼古丁不会减少预先注射高渗盐溶液的大鼠的饮水量。提示尼古丁可能通过中枢作用减少未被剥夺食物和水的大鼠的水摄入量。由于这种作用在重复测试中变化不大，它可能为该药物的一种或多种中枢作用提供有用的指标。
