Wellman Paul J, Bellinger Larry L, Cepeda-Benito Antonio, Susabda Agnes, Ho Dao H, Davis Kristina W
Behavioral Neuroscience Program, Department of Psychology, Texas A&M University, College Station, 77843-4235, USA.
Pharmacol Biochem Behav. 2005 Dec;82(4):627-34. doi: 10.1016/j.pbb.2005.11.002. Epub 2005 Dec 13.
Studies of the effects of nicotine (NIC) on meal patterns in rats often employ chow pellet diets that contain little fat, whereas humans using NIC commonly consume diets relatively rich in fat. The aim of the present study was therefore to compare the impact of NIC administration and NIC cessation on meal pattern in adult male rats offered a standard powdered chow (CHOW: 10.9% fat by calories) diet or a palatable high-fat (HIFAT: 58.3% fat by calories) diet. Computerized meal pattern analyses were conducted for male rats treated for 14 days with injections of either saline or 1.4 mg/kg/day of NIC (as the free base given in 5 equal amounts) during the dark phase and continued for 10 days after NIC cessation. The suppression of daily caloric intake by NIC was larger in HIFAT-NIC rats than in CHOW-NIC rats (p < .01), such that NIC induced a greater suppression of body weight in HIFAT-NIC rats, relative to CHOW-NIC rats (p < 0.02). NIC administration reduced MS in both CHOW and HIFAT rats. CHOW fed rats showed a gradual increase in meal number in response to NIC, whereas HIFAT fed rats showed a significant initial suppression of meal number, which returned to control levels by day 4 of the 14 day NIC treatment period. In addition, NIC increased water intake more in HIFAT fed rats than in CHOW rats. Cessation of NIC resulted in transient increases in daily caloric intake in CHOW and in HIFAT rats. The present study demonstrates that NIC actions on food intake suppression, meal patterns, and weight reduction differ depending on whether the rats are fed low- or high-fat diets.
关于尼古丁（NIC）对大鼠进食模式影响的研究通常采用脂肪含量低的饲料颗粒饮食，而使用尼古丁的人类通常食用脂肪含量相对较高的饮食。因此，本研究的目的是比较给予成年雄性大鼠标准粉状饲料（CHOW：热量的10.9%为脂肪）饮食或美味高脂肪（HIFAT：热量的58.3%为脂肪）饮食时，尼古丁给药和戒断对进食模式的影响。对在黑暗期接受14天注射生理盐水或1.4mg/kg/天尼古丁（作为游离碱，分5等份给予）治疗的雄性大鼠进行计算机化进食模式分析，并在尼古丁戒断后持续10天。与CHOW-NIC大鼠相比，HIFAT-NIC大鼠中尼古丁对每日热量摄入的抑制作用更大（p<0.01），因此，相对于CHOW-NIC大鼠，尼古丁在HIFAT-NIC大鼠中对体重的抑制作用更大（p<0.02）。给予尼古丁可降低CHOW和HIFAT大鼠的进食量。喂食CHOW的大鼠对尼古丁的反应是进食次数逐渐增加，而喂食HIFAT的大鼠在进食次数上最初有显著抑制，在14天尼古丁治疗期的第4天恢复到对照水平。此外，尼古丁对喂食HIFAT大鼠的水摄入量增加比对CHOW大鼠的更多。停止给予尼古丁导致CHOW和HIFAT大鼠的每日热量摄入短暂增加。本研究表明，尼古丁对食物摄入抑制、进食模式和体重减轻的作用因大鼠喂食的是低脂还是高脂饮食而异。
