http://www.jneurosci.org/content/32/27/9359.full

"L-DOPA (1 mg/ml) was administered in drinking water containing 0.25% ascorbic acid in applicable experiments. Solutions were prepared fresh daily and shielded from light. Pregnant and nursing dams had ad libitum access to L-DOPA/ascorbate or to ascorbate alone as a vehicle control. After weaning, pups continued to receive L-DOPA and ascorbate for 1.5–2.5 months. Some mice were subsequently withdrawn from L-DOPA for 1 month before testing."