Department of Pharmacology and Environmental Toxicology, Dr A.L.M. Postgraduate Institute of Basic Medical Sciences, University of Madras, Taramani Chennai 600 113, India.
Environ Toxicol Pharmacol. 1998 Nov 1;6(3):187-91. doi: 10.1016/s1382-6689(98)00033-7.
Spontaneous motor activity and motor coordination were tested in adult female rats after treating with sodium fluoride at 20 or 40 mg/kg dose level daily for 60 days, using an activity chamber and a rota-rod apparatus, respectively. Total protein concentrations were determined in skeletal muscle, liver and serum of similarly treated animals. The activities of total cholinesterase and acetylcholinesterase were determined in blood and brain regions, respectively. Sodium fluoride treatment suppressed spontaneous motor activity. But no change was observed in the motor coordination of these animals. Tissue and serum protein concentrations were decreased. Cholinesterase activity was decreased in the blood and not in brain regions. A failure of sodium fluoride to impair motor coordination indicated that neuromuscular function required for a forced task was not deteriorated in these animals, although skeletal muscles were deprived of protein and blood cholinesterase activity was suppressed. A suppression of spontaneous motor activity suggests that fluoride has, by a central action, inhibited motivation of these animals to exhibit locomotor behavior. A cholinergic mechanism through a change in the activity of acetylcholinesterase may not account for this effect, since sodium fluoride treatment did not alter the activity this enzyme in brain regions. However, an involvement of monoamines may be proposed in view of previously reported finding that excessive fluoride intake has decreased the concentrations of 5-hydroxyindoleacetic acid and increased that of norepinephrine in rat brain.
在 60 天的时间里，每天给雌性成年大鼠喂食 20 或 40mg/kg 剂量的氟化钠，分别用活动室和转棒仪测试其自发运动活动和运动协调能力。用同样的方法处理动物，检测其骨骼肌、肝脏和血清中的总蛋白浓度。分别在血液和脑组织中测定总胆碱酯酶和乙酰胆碱酯酶的活性。氟化钠处理抑制了自发运动活动，但这些动物的运动协调能力没有变化。组织和血清蛋白浓度降低，血液中的胆碱酯酶活性降低，但脑组织中的胆碱酯酶活性没有降低。氟化钠未能损害运动协调能力表明，这些动物进行强制任务所需的神经肌肉功能没有恶化，尽管骨骼肌失去了蛋白质，血液中的胆碱酯酶活性受到抑制。自发运动活动的抑制表明，氟化物通过中枢作用抑制了这些动物表现出运动行为的动机。通过改变乙酰胆碱酯酶的活性的胆碱能机制可能无法解释这种效应，因为氟化钠处理并没有改变大脑区域中这种酶的活性。然而，鉴于先前的研究结果表明，过量的氟摄入会降低大鼠大脑中 5-羟色胺乙酸和去甲肾上腺素的浓度，因此可以提出单胺类物质的参与。
