[Ultrastructure of the specialized intercellular contacts in an L-cell culture treated with low concentrations of lanthanum].

The electron microscope study of L-cells treated with 1 mM lanthanum has shown an increased amount of gap-like junctions and a decreased number of tight junctions compared to the norm. No damage in the plasma membrane structure and other cell organoids was observed. This may suggest that following the above treatment, the amplified intercellular exchange is associated with the increase in the quantity of intercellular highly permeable junctions. In this case lanthanum may serve as a membrane structure modificator. This effect must be taken into account when the electron microscopists use the lanthanum label for studying specialized intercellular junctions.