TH and Parkinson disease: Vehovszky et al. (2007) performed both acute test of rotenone (1–5 μM for 1–4 hr) and chronic test (0.5 μM for 4 days) on adult snails and found that rotenone induced significant reductions in spontaneous locomotion and feeding and decreased the tyrosine hydroxylase (TH) expression and dopamine level in the central nervous system. Maasz et al. (2017) selected young snail (not older than 3–4 months) and employed rotenone to induce PD model.