Role of parietal and principal gastric mucosa cells in the phenomenon of concentration of aluminum and indium

Laboratoire de Physiologie, Faculté de Médecine de Tunis (Université de Tunis El Manar), 15, Rue Djebel Lakhdar, La Rabta 1007, Tunis, Tunisia.
Microscopy Research and Technique (Impact Factor: 1.15). 02/2012; 75(2):182-8. DOI: 10.1002/jemt.21041
Source: PubMed


The subcellular behavior of aluminum and indium, used in medical and industrial fields, was studied in the gastric mucosa and the liver after their intragastric administration to rats, using, two of the most sensitive methods of observation and microanalysis, the transmission electron microscopy, and the secondary ion mass spectrometry. The ultrastructural study showed the presence of electron dense deposits, in the lysosomes of parietal and principal gastric mucosa cells but no loaded lysosomes were observed in the different studied hepatic territories. The microanalytical study allowed the identification of the chemical species present in those deposits as aluminum or indium isotopes and the cartography of their distribution. No modification was observed in control rats tissues. In comparison to previous studies describing the mechanism of aluminum concentration in the gastric mucosa and showing that this element was concentrated in the lysosomes of fundic and antral human gastric mucosa, our study provided additional informations about the types of cells involved in the phenomenon of concentration of aluminum and indium, which are the parietal and the principal cells of the gastric mucosa. Our study demonstrated that these cells have the ability to concentrate selectively aluminum and indium in their lysosomes, as a defensive reaction against intoxication by foreign elements.

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