Effects of maternal alcohol consumption during breastfeeding on motor and cerebellar Purkinje cells behavior in mice.

Purkinje cells (PCs) are the sole output from the cerebellar cortex. Their electrophysiological behavior may serve as indicator of chronic ethanol effects on the cerebellum. Here, we studied the effects of ethanol consumption through breastfeeding on motor behavior, histology and PCs electrophysiology. Mice with different maternal drinking regimen (ethanol, E or sucrose, S) during prenatal (E/and S/) and postnatal period (/E and/S) were compared. Motor performance in the runway and rotarod tests was significantly worse in mice exposed to ethanol prenatally (E/E and E/S) than in mice exposed to sucrose (S/S), with a limited influence, if any, of mother regimen during lactation (E/S vs E/E). A loss of 20-25% of PCs was found for both E/S and E/E compared to S/S mice but PC numbers were similar in S/E and S/S. Mean PC spontaneous simple spike firing rate and rhythmicity were higher in E/S and E/E than in S/S but there was no difference between S/E and S/S. Complex spike frequency was similar in all groups. In contrast, complex spike duration and the related pause induced on the simple spike firing were shorter in E/E and in E/S, but no difference was found between S/E and S/S. We conclude that cerebellar dysfunction induced by maternal ethanol consumption in mice depends upon the drinking regimen during pregnancy and not during lactation.