[Pathways of lanthanum ion transport across the posterior epithelium of the cornea in rabbits].

Morphological estimation of the barrier-transport properties of the posterior epithelium in the donor cornea has been performed in the most early time of fanoxic lesions of the cells. Ionized lanthanum, as an effective inhibitor of oxidative phosphorylation and simultaneously--as a marker of transport pathways for particles similar in their size to water molecule, is used in the investigation. The concentration gradient of rare-earth ions is produced by vital injection of lanthanum trichloride into the proper substance (stroma) of the cornea. From the microinjection focus the electron opaque marker is transported through the substrate of the basal substance of the stroma to the posterior epithelium and further along its intercellular and transcellular pathways into the anterior chamber of the eye. The rare-earth ions freely penetrate through the gap and tight junctions. Transcellular transport of lanthanum in the contents of the plasmolemmal microvesicles, vital absorption of the marker on the lateral and luminal parts of the plasmolemma and on the intracellular membranes, lesions of mitochondria and canaliculi of the endoplasmic reticulum of the anoxic character are stated. A suggestion is made on structural preservation of the pathways of convective and dissipative transition of the substance through the posterior epithelium of the cornea during the earliest time of the experimental anoxia.