A Histochemical Study of the Metabolism of Rat Renal Arteries and Arterioles

Abstract

A histochemical study of the metabolism of rat renal arteries and arterioles. Rat renal arteries and arterioles were examined histochemically to determine their metabolic profiles. Succinate, malate and NAD-isocitrate dehydrogenase, cytochrome oxidase and ubiquinone were assessed to determine aerobic metabolism. Glucose-6-phosphate dehydrogenase and DPN diaphorase were evaluated to determine hexosemonophosphate-shunt activity. Anaerobic metabolism was evaluated via lactate dehydrogenase, and the substrate, glycogen. Gomori's lipase, β-hydroxybutyrate dehydrogenase and amounts of neutral fat and free fatty acids were assessed as indicators of lipid utilization. Myosin ATPase activity was evaluated as an index of ATP utilization for contraction. Deoxyribonucleic and ribonucleic acids were appraised as indicators of protein synthesis. In general, the oxidative enzymes and myosin ATPase demonstrate considerable activity in renal arteries and arterioles which suggests aerobic metabolism and ATP usage. Renal arteries and arterioles also appear capable of anaerobic metabolism as indicated by strong lactate dehydrogenase reactivity and by the presence of slight to moderate quantities of glycogen, while high levels of glucose-6-phosphate dehydrogenase and moderate amounts of deoxyribonucleic acid suggest a potential for nucleic acid and protein synthesis. In arteries and arterioles, strong reactivity for β-hydroxybutyrate dehydrogenase, minimal lipase activity, and the absence of fatty acids with substantial amounts of neutral fat, indicate limited lipid catabolism.