The Effect of Phenylthiourea on Pigmentation by Melanin in the Developing Frog, Eleutherodactylus martinicensis
نویسنده
چکیده
The black pigment cells in the skin, iris, and retina of Eleutherodactylus martinicensis (Tschudi) are melanophores. Under the influence of c o 1 per cent, phenylthiourea the melanin disappears in about 84 hours at laboratory temperatures. After administration of the substance for 5 days, discontinuance of treatment is followed by return of the pigment within 72 hours, to an extent at least equal to that normally attained in untreated controls. The stages of disappearance and reappearance of this pigment have been studied in the gross embryo, skin, iris, and retina, as well as in individual melanophores.
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