These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Fine structural demonstration of tyrosinase activity in the retinal pigment epithelium of normal and PTU-treated chick embryos.
    Author: Mishima H, Hasebe H, Kondo K, Fujita H.
    Journal: Albrecht Von Graefes Arch Klin Exp Ophthalmol; 1979 Jul 02; 211(1):1-10. PubMed ID: 111576.
    Abstract:
    The effect of phenylthiourea (PTU) on the retinal pigment epithelium of chick embryo was studied by using electron microscopy and electron-microscopic histochemistry. In the retinal pigment epithelium of PTU-treated, 10-day-old chick embryo, there is an abundance of premelanosomes and relative increases in the smooth endoplasmic reticulum (ER), and in the smooth-surfaced anastomosing tubular channels. Reaction products resulting from electron-microscopic histochemistry are first observed in some cisternae of the distal or active face of the Golgi apparatus and occasionally in small vesicles in the 5-day-old embryo, and these reactions become more intense with time. PTU treatment blocks melanin synthesis in the premelanosomes of 10-day-old chick embryo. Electron-microscopic histochemistry is completely inhibited by PTU treatment. Removal of PTU allows a weak positive reaction to histochemistry in some elements of the Golgi apparatus and in some small vesicles.
    [Abstract] [Full Text] [Related] [New Search]