Melanophores


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Related to Melanophores: Iridophores, Xanthophores

Melanophores

 

in cold-blooded vertebrates, pigment cells containing melanin granules; the last stage in the differentiation of melanocytes.

Melanophores are large dendritic cells that respond to changes in light or to the pituitary melanocyte-stimulating hormone by changing color. This change reflects the alteration of the dispersion of the pigment granules in the cytoplasm. Melanophores cannot divide, migrate, or synthesize tyrosinase, the specific enzyme necessary for melanin synthesis. Together with other chrotnatophores, they make up part of a system responsible for rapid changes in skin color in a number of animals, including many fishes, amphibians, and chameleons.

REFERENCE

Fitzpatrick, T. B. “Terminology of Vertebrate Melanin-containing Cells.” Science, 1965, vol. 152, pp. 88–89.
References in periodicals archive ?
Morphological features, including the development of the opercular complex and head spination, the sequence of development of meristic characters, and the position and relative size of the melanophores in preflexion, flexion, and postflexion larvae, allowed reconstruction of a developmental series and identification of the remaining individuals studied as A.
Carapace in males with inverted, dark, triangular patch of melanophores on dorsal surface of both left and right alae (much more apparent at lower magnifications) as well as scattered melanophores on alae and diffuse pigment scattered on cephalic region.
Helcogramma steinitzi a des melanophores seulement sur la moitie distale de l'anale (dans les deux autres especes, les melanophores couvrent toute la nageoire) et un interorbital etroit (166 dans le sens de la longueur de la tete).
However, the actual extent of the effect of each of these other compounds alone or in combination with MSH is not known, making previous work on melanophores and pituitary extracts unclear.
Lower jaw protruding slightly, mouth of holotype forming an angle of about 32 degrees with longitudinal axis of body; jaw extending to level of anterior edge of pupil; teeth of jaws numerous, in dense bands, outer row enlarged; palate edentulous; tongue, palate and floor of mouth generally pale with faint melanophores.
Stellate melanophores were scattered around the outside of the yolk.
Some are simple units made of melanophores and leucophores, or melanophores and iridophores, and the synergistic action of the chromatophores that form these simple units responding to neural changes is the basis of rapid color changes (Herring 1994, Fujii et al.
The eyes are partially pigmented; a patch of larger melanophores is present on the anterodorsal quadrant and smaller fine melanophores are scattered over the dorsal half of the eye and concentrated along the upper rim of the lens (Fig.
Pectoral-fin base rarely with prominent C glaucofraenum dark marking ventrally, although melanophores may form one to three light to moderate concentrations on base; body with three rows of dark markings, most of those in the lower row large, distinctive X-shaped markings; pigment marking above opercle usually with two well-defined peaks 4a.
The pigment pattern from preflexion to juvenile stage consists of three bands on the dorsal margin and two bands on the ventral margin formed by star-shaped melanophores on the left side of the body.