Lipofuscin-like pigments in endocardial cells enveloping the heart muscle trabeculae in platyfish (Poeciliidae: Teleostei)

Abstract

Large amounts of lipofuscin-like pigments were demonstrated by means of the Schmorl's technique in endocardial cells enveloping the heart muscle trabeculae in adult platyfish (Xiphophorus maculatus). Such pigment granules occurred in a low number in the corresponding cell layers in the heart of 6-mm long prenatal platies. The endocardial cells contained numerous lysosome-like bodies, bristle-coated vesicles, and tubules of agranular endoplasmic reticulum, particularly in adult specimens. The lipofuscin-rich endocardial cell layers displayed deep blue precipitations in hearts from the ferritin-injected adult platies 6 h or more post-injection, when treated with acid ferrocyanide instead of Schmorl's solution, i.e., this cell type is able to take up foreign particles. The occurrence of much lipofuscin-like pigments in endocardial cell layers in adult platies provides evidence that these cells have performed important scavenger functions at this stage of development. © Springer Science+Business Media, Inc. 2007.