Laboratório de Neurofisiologia, Departamento de Ciências Fisiológicas, Instituto de Biologia Roberto Alcantara Gomes, Centro Biomédico, Universidade do Estado do Rio de Janeiro, Av. Prof. Manoel de Abreu 444, 5 degrees andar, Vila Isabel, Rio de Janeiro, RJ, 20550-170, Brazil.
Nicotine Tob Res. 2010 Jul;12(7):776-80. doi: 10.1093/ntr/ntq075. Epub 2010 May 10.
There is a lack of experimental studies that investigate the effects of tobacco smoke exposure during adolescence. Here, we investigated the effects of tobacco smoke generated from cigarettes containing either high or low levels of nicotine on the cholinergic system.
From postnatal day (PN) 30 to 45, 18 C57BL/6 (inbred) and 16 Swiss (outbred) mice of both sexes were exposed to tobacco smoke (whole body exposure for 8 hr/day and 7 days/week) generated from one of two reference research cigarettes: type 3R4F (HighNIC group-nicotine = 0.73 mg/cigarette) or type 4A1 (LowNIC group-nicotine = 0.14 mg/cigarette). Control mice (CT) were exposed to air. On PN 45, cotinine (nicotine metabolite) serum levels and [(3)H]choline uptake in the cerebral cortex and hippocampus were assessed.
Cotinine serum levels were eight times higher in HighNIC mice (C57BL/6:142.0 +/- 16.7 ng/ml and Swiss: 197.6 +/- 11.1 ng/ml) when compared with LowNIC ones (C57BL/6:17.4 +/- 7.4 ng/ml and Swiss: 24.6 +/- 2.2 ng/ml). Only HighNIC mice presented a significant increase in [(3)H]choline uptake in the hippocampus (C57BL/6: HighNIC > CT and HighNIC > LowNIC, p < .001 and Swiss: HighNIC > CT and HighNIC > LowNIC, p < .001), whereas in the cerebral cortex, both HighNIC and LowNIC mice presented increased [(3)H]choline uptake (C57BL/6: HighNIC > CT and LowNIC > CT, p < .05 and Swiss: HighNIC > CT and LowNIC > CT, p < .001).
Our results indicate that tobacco smoke exposure during adolescence increases [(3)H]choline uptake. However, the effects are dependent on the type of cigarette and on the brain region.
目前缺乏研究青少年时期暴露于烟草烟雾的实验。在这里，我们研究了来自两种参考研究香烟之一的烟草烟雾对胆碱能系统的影响，这两种香烟分别含有高水平和低水平的尼古丁。
从出生后第 30 天到第 45 天，18 只 C57BL/6（近交系）和 16 只瑞士（远交系）雌雄小鼠接受两种参考研究香烟之一的烟草烟雾全身暴露（每天 8 小时，每周 7 天）：3R4F 型（高尼古丁组-尼古丁=0.73mg/支）或 4A1 型（低尼古丁组-尼古丁=0.14mg/支）。对照小鼠（CT）暴露于空气中。在第 45 天，评估血清中的可替宁（尼古丁代谢物）水平和大脑皮层及海马中的[3H]胆碱摄取。
与低尼古丁组相比，高尼古丁组的血清可替宁水平高 8 倍（C57BL/6：142.0±16.7ng/ml 和瑞士：197.6±11.1ng/ml）。只有高尼古丁组的海马中[3H]胆碱摄取显著增加（C57BL/6：高尼古丁>CT 和高尼古丁>低尼古丁，p<0.001 和瑞士：高尼古丁>CT 和高尼古丁>低尼古丁，p<0.001），而在大脑皮层中，高尼古丁和低尼古丁组的[3H]胆碱摄取均增加（C57BL/6：高尼古丁>CT 和低尼古丁>CT，p<0.05 和瑞士：高尼古丁>CT 和低尼古丁>CT，p<0.001）。
我们的结果表明，青少年时期暴露于烟草烟雾会增加[3H]胆碱摄取。然而，这些影响取决于香烟的类型和大脑区域。
