Behavioural multigenerational effects induced by the administration of very low doses of zinc during pregnancy, lactation, and prepuberal period in the rat

In studies from this laboratory, the chronic administration of ZnTe during pregnancy, lactation, and prepuberal stages of litter (F₁ generation) modified the behavioral patterns of motivated exploration, lateralized exploration, social activity, and survival responses of maturing rats. To determine whether these affected behaviors would extend to the next generation, F₁ litter rats previously exposed to tellurium (Te) up to 30-day-old were left at rest with no further treatment up to 90-day-old. Then, F₁ female rats were mated with normal untreated male rats, and in the next generation (F₂), the litter rats at 30-day-old preserved the modified behaviors previously observed in their parents. The study revealed that Te effects were intergenerational. Here, considering that ZnTe was used in the previous study and that Zn ion has many physiological functions in the cell, experiments were conducted to elucidate if Zn would have an intergenerational effect similar to Te. Working with the same experimental setup as in the previous study but using ZnCl₂ instead of ZnTe, results revealed that none of the behavioral responses studied were affected by the F₁ generation. However, in the F₂ generation, lateralized exploration and survival behavior were inhibited, suggesting that Zn also has an intergenerational effect.