Immunohistochemical detection of hepatic GM1 and GM2 gangliosides in streptozotocin-induced diabetic rats.

This study was undertaken to investigate the consequences of diabetes on the expression of GM1 and GM2 gangliosides in rat liver. Experimental diabetes was induced by treatment with Streptozotocin (STZ) in adult male Sprague-Dawley rats. Two-dimensional thin-layer chromatography of total ganglioside preparations of liver tissues from STZ-induced diabetic rats showed an increased amount of GM1, while GM2 could not be detected.

Ultrastructural characteristics of the follicle cell-oocyte interface in the oogenesis of Ceratophrys cranwelli.

In this work we carried out an ultrastructural analysis of the cell interface between oocyte and follicle cells during the oogenesis of the amphibian Ceratophrys cranwelli, which revealed a complex cell-cell interaction. In the early previtellogenic follicles, the plasma membrane of the follicle cells lies in close contact with the plasma membrane of the oocyte, with no interface between them. In the mid-previtellogenic follicles the follicle cells became more active and their cytoplasm has vesicles containing granular material.