A behavioural study has been conducted in mice concerning reserpine catatony and possible reversal of the same by L-Dopa or S-Adenosylmethionine alone or together. Our results show no differences in the reversal of reserpine catatony among animals treated with L-Dopa, S-Adenosylmethionine, L-Dopa + S-Adenosylmethionine or saline, the motor patterns being evaluated with a Catatony Rating Scale (CRS). Some considerations are taken into account as possible explanations. The lack of reversal of chronic reserpine catony in mice by L-Dopa shows that this model is not perfectly comparable to Parkinson's disease.