[Ultrastructure of rat proximal renal tubular epithelium during the secretion of cardiotrast].

Within a 15 minutes' cardiotrast secretion, following its intravenous injection, diametres of cisterns of the endoplasmic reticulum and of the Golgi complex were shown to enlarge in the epithelial cells of the rat nephron proximal canal epithelial cells. Later on, the enlargement of the intracellular space and the space between infoldings of the plasmatic membrane of cell basement occurred; besides the mitochondrial structure was changed too. The increased size of microbodies was characteristic of cardiotrast-secreting cells.