Pigmented Hyperplasia of Epidermis Following Feeding of l-Dopa to Elderly Rats

Abstract

In view of clinical data supporting a causal relationship between long-term l-dopa administration and recurrence of melanoma, long-term l-dopa administration to aged rats was performed to investigate its effect on the incidence of malignant melanoma. Of the treated animals, 11% showed local pigmented epidermal hyperplasia, compared with 0.5% of the control animals, but the number of expected melanomas was not increased by l-dopa treatment.