Origen de las concreciones minerales intestinales de copépodos parásitos. Estudio microanalítico y ultraestructural

Abstract

Origin of the mineral concretions of the midgut cells of parasitic copepods. A microanalytic and ultrastructural study
A certain cell type exists in the midgut of parasitic copepods denominated the vacuolated cells, characterized by a reduction in the microvilli. The vacuoles of the apical area are extremely polymorphic and numerous intracytoplasmatic mineral concretions are observed as being part of them. The vesicles of the rough endoplasmic reticulum and ocasionally the mitochondria and the Golgi complex constitutes the organic matrix of the spherocrystals. The elemental composition of the mineral concretions in their stage of maximum consolidation was studied using the energy-dispersive X-ray microanalysis techniques. The most abundant constituent elements observed were Ca, Mg, Na, P. Fe and Zn. The interrelationship, between the spherocrystals and the vacuoles is discussed in this paperas is their possible functional significance. It may consist of a pathway to element storage for those elements which, like calcium, contribute to the formation of the new cuticle. On the other hand, it may have a strictly excretory significance, through inactivation of the different mineral elements whilst within the interior of these intestinal cells.