Shafiq-ur-Rehman S
Division of Environmental Sciences, Sher-e-Kashmir University of Agricultural Sciences and Technology, Kashmir, India.
Arch Environ Contam Toxicol. 1991 May;20(4):527-30. doi: 10.1007/BF01065844.
The behavioral complex stereotype responses such as rearing, preening, scratching and biting were observed in an open-field situation in rats ingesting 2% lead acetate in drinking water for a period of 30 days. Endogeneous levels of dopamine were measured spectrophoto-fluorometrically in three brain regions; namely, cerebral cortex, cerebellum, and brain stem. The behavioral rearing response was diminished on day 3 and between days 7 to 22 of lead ingestion as compared to the control. Subsequently, this response was progressively increased from day 26 to 30. The animals showed depressed response of preening on day 2 and 6. From day 9, the preening response exhibited a continuous increasing pattern until the last day of the experiment. However, the complex stereotypy of scratching behavior of rats showed a parabolic pattern against the normal scratching behavior. A similar pattern of biting response has been observed in lead-intoxicated animals. Both the scratching and biting responses were higher than the control at the end of the experiment. Dopamine levels increased in the cerebral cortex on days 13, 23, and 30. In the cerebellum, the dopamine level was reduced on day 13 and increased on day 23. The brain stem exhibited increased level of dopamine on days 3, 13, 23, and 30 as compared to the control. These evidences clearly show an association of dopamine with complex stereotypy behaviors of lead intoxication.
在饮用含2%醋酸铅的水30天的大鼠的旷场实验中，观察到了诸如竖尾、理毛、抓挠和啃咬等行为复杂的刻板反应。采用分光光度荧光法测量了大脑三个区域，即大脑皮层、小脑和脑干中的内源性多巴胺水平。与对照组相比，在摄入铅的第3天以及第7至22天期间，行为竖尾反应减弱。随后，从第26天到第30天，这种反应逐渐增强。动物在第2天和第6天表现出理毛反应降低。从第9天开始，理毛反应呈现持续增加的模式，直至实验最后一天。然而，大鼠抓挠行为的复杂刻板表现相对于正常抓挠行为呈现出抛物线模式。在铅中毒动物中也观察到了类似的啃咬反应模式。在实验结束时，抓挠和啃咬反应均高于对照组。在第13天、23天和30天，大脑皮层中的多巴胺水平升高。在小脑中，多巴胺水平在第13天降低，在第23天升高。与对照组相比，脑干在第3天、13天、23天和30天的多巴胺水平升高。这些证据清楚地表明多巴胺与铅中毒的复杂刻板行为之间存在关联。
