Department of Medical Physiology, Medical Division, National Research Center, El-Buhouth St., Dokki, Giza, Egypt.
Eur Rev Med Pharmacol Sci. 2011 Aug;15(8):863-70.
A number of studies have shown that nicotine has an antidepressant-like effect. The prevalence of smoking is much higher in people suffering from depression. In addition, the administration of nicotine from transdermal nicotine patch can exert antidepressant activity in nonsmokers and the continuous infusion of nicotine to rats attenuates learned helplessness, a putative behavioral model of depression. The aim of the present study is to elucidate the neurochemical effect of nicotine on monoamine levels in the cerebral cortex and hippocampus of reserpinized rats as a model of depression.
In the present study, rats were divided into control animals treated with saline and reserpinized group which received a daily i.p injection of reserpine for 15 days to establish the animal model of depression. Starting from the 16th day, the reserpinized rats were divided into reserpinized rats, and reserpinized rats treated daily with nicotine (0.4 mg/kg) for 15 and 30 days. After decapitation, the cerebral cortex and hippocampus of each rat were dissected out. The levels of monoamine neurotransmitters (serotonin, norepinephrine and dopamine) were measured in each area using a spectrofluorimeter.
The daily i.p injection of reserpine induced a significant decrease in monoamine levels in the cortex and hippocampus. Nicotine administration restored the changes in monoamine neurotransmitters induced by reserpine in both areas after 30 days.
The data of the present study suggest that the antidepressant-like effect of nicotine could be mediated by the effect of nicotine on monoamine neurotransmitters in the cortex and hippocampus of rat brain.
多项研究表明，尼古丁具有抗抑郁作用。患有抑郁症的人群中，吸烟的比例要高得多。此外，经皮尼古丁贴片给予尼古丁可在非吸烟者中发挥抗抑郁作用，并且向大鼠持续输注尼古丁可减轻习得性无助，这是一种潜在的抑郁行为模型。本研究的目的是阐明尼古丁对抑郁模型（即利血平化大鼠）大脑皮质和海马中单胺水平的神经化学作用。
在本研究中，大鼠分为生理盐水处理的对照组和连续 15 天每天腹腔注射利血平以建立抑郁动物模型的利血平化组。从第 16 天开始，利血平化大鼠分为利血平化大鼠和利血平化大鼠，每天给予尼古丁（0.4mg/kg）治疗 15 天和 30 天。断头后，从每个大鼠中取出大脑皮质和海马。使用荧光分光光度计测量每个区域中单胺神经递质（5-羟色胺、去甲肾上腺素和多巴胺）的水平。
每天腹腔注射利血平会导致皮质和海马中单胺水平显著降低。尼古丁给药 30 天后可恢复利血平诱导的两种区域中单胺神经递质的变化。
本研究的数据表明，尼古丁的抗抑郁样作用可能是通过尼古丁对大鼠大脑皮质和海马中单胺神经递质的作用介导的。
