Abstract
Methylmercury chloride (MMC) was given to pregnant rats on the 6th, 7th, 8th, and 9th day after conception in doses of 0.05 and 2.0 mg/kg/day. The female offspring of these animals were tested 90 days after birth for learning ability using operant conditioning procedures. The rats were kept at 90% of their normal body weight and trained in a lever-box to press a bar in order to obtain a food pellet.
Significant differences in the acquisition speed became apparent when the ratio of bar presses to reward was increased in a classical contingency of differential reinforcement of high rates even at MMC-doses of 4 × 0.05 mg/kg. These differences were not found in the general motility level nor in motor coordination.
Zusammenfassung
Trächtige Ratten erhielten am 6., 7., 8. und 9. Tag der Gravidität Methylquecksilberchlorid (MMC) in Dosen von 0,05 und 2,0 mg/kg/Tag. Die weiblichen Nachkommen dieser Tiere wurden 90 Tage nach der Geburt mit Hilfe der Konditionierung operanten Verhaltens auf ihre Lernfähigkeit hin getestet. Die Tiere wurden auf 90% ihres Normalgewichtes herabgesetzt. In einer Skinnerbox wurden sie darauf trainiert, für den Erhalt von Futter einen Hebel zu drücken.
Signifikante Unterschiede traten bereits nach 4 × 0,05 mg/kg MMC auf, wenn die Tiere in dem klassischen Konditionierungsprogramm “Differential Reinforcement of High Rates” den Hebel innerhalb einer vorbestimmten, kurzen Zeitspanne zunehmend häufig drücken mußten, um Futter zu erhalten. Die allgemeine Motilität und die motorische Koordination waren unverändert.
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Müsch, H.R., Bornhausen, M., Kriegel, H. et al. Methylmercury chloride induces learning deficits in prenatally treated Rats. Arch Toxicol 40, 103–108 (1978). https://doi.org/10.1007/BF01891964
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DOI: https://doi.org/10.1007/BF01891964