Sershen H, Reith M E, Banay-Schwartz M, Lajtha A
Neurochem Res. 1982 Dec;7(12):1515-22. doi: 10.1007/BF00965094.
The effects of nicotine on brain protein metabolism and on the properties of the nicotine binding site were investigated in newborn animals exposed to nicotine during gestation. Brain protein synthesis rates measured in vivo were lower by 18% in newborn of treated animals. Protein degradation rates measured in vitro in the presence of nicotine were lower by 13%. The effect was specific for L-(-)nicotine, since D-(+)nicotine, nicotinic acid, or nicotinamide had no effect on degradation rates. Newborn brain amino acid levels, mainly nonessential amino acids and amino acids of putative neurotransmitter function, were changed somewhat; an increase in the level of taurine (13%), threonine (21%), serine (35%) and glycine (35%), and a decrease in lysine (14%) was observed in the offspring of nicotine treated animals (0.5 mg/kg, s.c., 2 x daily throughout gestation). These changes could not account for the decrease in protein metabolism. Nicotine binding was higher by 25% in the offspring of animals exposed to nicotine during gestation. No such increase was found after treatment of adult rats with nicotine, indicating that the properties of the nicotine binding site change with age.
研究了尼古丁对孕期暴露于尼古丁的新生动物脑蛋白代谢及尼古丁结合位点特性的影响。经处理动物的新生幼崽体内测得的脑蛋白合成率降低了18%。在尼古丁存在的情况下体外测得的蛋白降解率降低了13%。该效应具有L-(-)尼古丁特异性，因为D-(+)尼古丁、烟酸或烟酰胺对降解率无影响。新生脑氨基酸水平，主要是非必需氨基酸和具有假定神经递质功能的氨基酸，有一定变化；在经尼古丁处理的动物（0.5mg/kg，皮下注射，孕期每天2次）后代中观察到牛磺酸（13%）、苏氨酸（21%）、丝氨酸（35%）和甘氨酸（35%）水平升高，赖氨酸（14%）水平降低。这些变化无法解释蛋白代谢的降低。孕期暴露于尼古丁的动物后代中尼古丁结合率高25%。成年大鼠用尼古丁处理后未发现此类增加，表明尼古丁结合位点的特性随年龄变化。
