Lead (Pb) is a non physiological metal that has been implicated in toxic processes affecting several organs and biological systems, including the central nervous system. Several studies have focused on changes in lead-associated neurobehavioral and neurochemical alterations that occur due to Pb exposure. The present study evaluates the effects of acute and chronic Pb acetate exposure on serotoninergic and dopaminergic systems within the dorsal raphe nucleus, regarding motor activity and anxiety behaviours. Experiments were carried out on adult male Meriones shawi exposed to acute lead acetate intoxication (25 mg/kg b.w., 3 i.p. injections) or to a chronic lead exposure (0,5 %) in drinking water from intrauterine age to adult age. Immunohistochemical staining demonstrated that both acute and chronic lead exposure increased anti-serotonin (anti-5HT) and tyrosine hydroxylase (anti-TH) immuno-reactivities in the dorsal raphe nucleus. In parallel, our results demonstrated that a long term Pb-exposure, but not an acute lead intoxication, induced behavioural alterations including, hyperactivity (open field test), and anxiogenic like-effects. Such neurobehavioral impairments induced by Pb-exposure in Meriones shawi may be related to dopaminergic and serotoninergic injuries identified in the dorsal raphe nucleus.

中文翻译：

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沙漠啮齿动物 Meriones shawi 急性和慢性铅暴露对神经行为的影响：血清素和多巴胺的参与

铅 (Pb) 是一种非生理金属，与影响多个器官和生物系统（包括中枢神经系统）的毒性过程有关。几项研究集中在铅暴露引起的与铅相关的神经行为和神经化学改变的变化上。本研究评估急性和慢性醋酸铅暴露对中缝背核内的血清素能和多巴胺能系统的影响，涉及运动活动和焦虑行为。对暴露于急性醋酸铅中毒（25 毫克/千克体重，3 次腹腔注射）或慢性铅暴露 (0.5%) 的成年雄性 Meriones shawi 从宫内龄到成年期的饮用水中进行了实验。免疫组织化学染色表明，急性和慢性铅暴露都会增加中缝背核中的抗血清素（抗 5HT）和酪氨酸羟化酶（抗 TH）免疫反应性。同时，我们的结果表明，长期接触铅，而不是急性铅中毒，会引起行为改变，包括多动（露天试验）和产生焦虑的类似效应。在 Meriones shawi 中由铅暴露引起的这种神经行为障碍可能与中缝背核中发现的多巴胺能和血清素能损伤有关。和产生焦虑的类似作用。在 Meriones shawi 中由铅暴露引起的这种神经行为障碍可能与中缝背核中发现的多巴胺能和血清素能损伤有关。和产生焦虑的类似作用。在 Meriones shawi 中由铅暴露引起的这种神经行为障碍可能与中缝背核中发现的多巴胺能和血清素能损伤有关。