Renal cortical cells in primary monolayer culture

Abstract

Renal cortical tubules and epithelial cells, prepared with high yield and viability (>98%) by a rapid isolation procedure of pre-perfusing the kidneys with a Ca2+-chelator and subsequent submission of the cortices to an improved slicing technique, were maintained in primary monolayer culture. The activities of several maker enzymes exhibited a distribution very similar to that of the intact kidney cortex tissue: phosphate-dependent glutaminase (mitochondria), glutamate dehydrogenase (mitochondria), cytochrome oxidase (mitochondria), lactate dehydrogenase (cytoplasm), γ-glutamyltranspeptidase (brush border membrane), and alkaline phosphatase (brush border membrane). The cells show a well-differentiated and preserved ultrastructure even after several days in culture. Changes in kidney-specific enzyme activities were determined in monolayer cells for up to 8 days. Renal conical cells isolated from acidotic rats exhibited elevated levels of glutamate dehydrogenase and phosphate-dependent glutaminase. The elevated dehydrogenase activity was retained in culture. In contrast, the induced glutaminase activity was found to be labile. The system developed here should prove suitable for various in vivo/in vitro comparative studies, and it may have considerable potential for the characterization of the regulation of a variety of kidney-specific processes.