Propanediol-induced alterations in membrane integrity, metabolism and developmental potential of mouse zygotes

The effects of 1,2-propanediol (PROH) on embryonic development, membrane integrity and metabolism on B6D2F1 mouse zygotes in the pronuclear stage were evaluated. In both the control and the group treated with 1.5 M PROH, 78% of the zygotes developed into 2-cell embryos. With 3 M PROH, the proportion of 2-cell embryos was only 7% (P less than 0.05). In a second series of experiments, pronuclear mouse eggs were incubated in either fluorescein diacetate (FDA) or 5 microM Acridine Orange (AO) then transferred to PROH. FDA-induced fluorescence, which is maintained until the cell membrane is damaged, was retained in 100% of the control and 98% of the zygotes treated with 1.5 M PROH. Exposure to 3.0 and 6.0 M PROH reduced the percentage of zygotes with FDA-induced fluorescence to 81% (P less than 0.05) and 5% (P less than 0.05) respectively. AO fluoresces yellow-green within the physiological pH range (7.4). After AO exposure, 95% of the control zygotes and 95% of the zygotes exposed to 1.5 M PROH possessed yellow-green fluorescence, indicating a normal cellular pH. Treatment with 3.0 and 6.0 M PROH caused a shift in the fluorescence such that 93% (P less than 0.05) and 100% (P less than 0.05) of the zygotes respectively no longer fluoresced yellow-green, indicating a lower pH. These results demonstrate that a 20-min exposure to 1.5 M PROH does not affect embryonic development, while PROH at greater than or equal to 3.0 M inhibits embryonic development.(ABSTRACT TRUNCATED AT 250 WORDS)