Melanomacrophage Aggregations and Their Age Relationships in the Yellow Mud Turtle, Kinosternon flavescens (Kinosternidae)

Abstract

Microscopic examination of the pigment cell aggregations in the liver and spleen of mud turtles (Kinosternon flavescens) suggests that the morphology and behavior of these cells is consistent with the melanomacrophages described in teleost fishes and the pigmented "Kupffer cells" described in frogs and reptiles. These cells contain massive amounts of melanin, substantial lipofuscin, and some hemosiderin consistent with their phagocytic function. Similar-appearing isolated pigmented macrophages are solitary in the liver, spleen, lung, and kidney. Number and size of the largest hepatic aggregations increase almost linearly with turtle age so that in old turtles they may constitute up to 20% of the liver volume. This increase may result from hepatic recruitment of macrophages throughout the life of the turtle and suggests that size and number of melanomacrophage aggregations may serve as a marker for senescence in otherwise healthy turtles of this species.

Histological description of the reproductive tract of male and female hatchlings of the Magdalena river turtle (Podocnemis lewyana).

“…2B) is compatible with the melano-macrophage centers (MMC), which are aggregations of macrophages with melanin, lipofuscin and hemosiderin. These MMC have been found in spleen, liver, and gonads of other vertebrates such as fish, frogs and even Kinosternon turtles (Ravaglia and Maggese, 1995;Christiansen et al, 1996;Agius and Roberts, 2003;Pérez, 2010). Among the functions of MMC are antibacterial protection and phagocytosis, and their amount can vary with the external environment including contamination (Pérez, 2010), but also with nutrition and hormones according to the reproductive cycle (Agius and Roberts, 2003).…”

The Antimicrobial Properties of Melanocytes, Melanosomes and Melanin and the Evolution of Black Skin

“…For example, there exist a class of melanin-containing macrophage called melanomacrophages that occur in a diverse range of species including reptiles, amphibia and "sh (Johnson et al, 1999;Christiansen et al, 1996;Rund et al, 1998;Rocha et al, 1997;Palenzuela et al, 1999;Eng & Youson, 1992). In these animals melanomacrophages are recognized as an important component of the innate immune defense system against protozoan and bacterial pathogens.…”

Pigmentação testicular em Physalaemus nattereri (Steindachner) (Amphibia, Anura) com observações anatômicas sobre o sistema pigmentar extracutâneo

“…Segundo alguns autores, além da cútis, células pigmentares contendo melanina são encontradas em diversas vísceras de répteis e anfíbios como no fígado, rins, baço, peritônio, ouvido, encéfalo, ao redor de nervos e vasos sangüíneos, com diferentes ocorrências, tipos e quantidade em diferentes espécies (AOKI et al 1969, GEREMIA et al 1984, GOPALAKRISHNAKONE 1986, CICERO et al 1989, PEDERZOLI & TREVISAN 1990, TREVISAN et al 1991, ZAGAL'SKAIA 1994, SICHEL et al 1997, AKULENKO 1998, ZUASTI et al 1998, CHRISTIANSEN et al 1996, RUND et al 1998, JOHNSON et al 1999, OLI-VEIRA et al 2002, 2003. Estas células podem ser agrupadas constituindo um sistema melanogênico cuja função não está devidamente esclarecida (ZUASTI et al 1998).…”