[Dynamics of the redistribution of pigment granules in the dermal melanophores of anuran amphibians. 1. Dispersion]. / Dinamika pereraspredeleniia pigmentnykh granul v dermal'nykh melanoforakh beskhvostykh amfibii. 1. Dispersiia.

The dispersion of melanosomes in the dermal melanophores of the Xenopus laevis larvae has been studied by time--lapse cinematography. The process began with the appearance of distally directed melanosome flows in the cell cytoplasm. During the subsequent migration of pigment granules, the flows branched forming branches of the 2nd and higher orders. The whole cytoplasm became filled with a layer of melanosomes. During the dispersion, the movement of melanosomes in a flow is replaced by their dispersion all over the cytoplasm; these processes alternated. In the peripheral part of the cell devoid of melanosomes, membrane vesicles appeared and the cytoplasm was distinctly divided into ecto- and endoplasm. The ectoplasm contained numerous microfilaments and single microtubules, the endoplasm did not contain any cell organelles, except single electron-dense melanosomes. The active role of plasma membrane in the intracellular movement of melanin granules is suggested.

[Ultrastructural changes in dermal melanophores in the process of pigment granule migration]. / Izmenenie ul'trastruktury dermal'nykh melanoforov v protsesse migratsii pigmentnykh granul.

The results of electron microscope investigations on dermal melanophores of Rana temporaria L. during migration of pigment granules are presented. It was shown that in comparison to the previous observations dermal melanophores are flat cells without branches. Ultrastructural differences have been demonstrated in dermal melanophores during migration of pigment granules. During melanosome dispersion membrane vesicle bodies are seen in the cytoplasm to be inserted in the melanophore membrane.