Late embryonic exposure to all-trans retinoic acid induces a pattern of motor deficits unrelated to the developmental stage

The present study extends previous investigations examining the behavioral outcomes of all-trans retinoic acid (RA) exposure at embryonic (E) days 14–16. A sublethal dose (2.5 mg/kg b.w.) compatible with high neonatal survival sufficient to supply offspring for later behavioral testing, was used. The results show that E14–16 RA exposure, similar to E8–10 or E11–13 (previous studies), impairs locomotor activity (open field test) as well as motor coordination and motor learning (rotarod/accelerod task) in young-adult rats. The results provide further evidence that RA exposure induces a pattern of motor deficits which are not strictly related to the embryonic stage, compatible with the protracted developmental profile of the cerebellum.