Previous histo-and biochemical studies of mucosal metabolism during acute sinusitis indicate that the shortage of mucosal energy is mainly due to an inadequate oxygen supply and not to a decrease in the oxidative enzyme capacity of the mucosal
epithelium. The high lactate concentration found in purulent sinus secretion is the result of leukocyte glycolysis.
The purpose of this study was to analyze the metabolism of the regional mucosa in the nose and sinuses by the histochemical localization and semi-quantification of the enzymes : actate dehydrogenase(LDH), succinate dehydrogenase(SDH), and
adenosine
triphosphatase(ATPase). The nose and sinus complex from five healthy new Zealand white rabbits, and three rabbits which had the control side from a series of rabbits with contralateral acute sinusitis, embedded in carboxymethylcellulose and
frozen,
was
serially sectioned in a freezing microtome. Sections 20-μm thick were incubated to determinate their LDH, SDH and ATPase activity with their corresponding substrates, and examined by light microscopy. Controls were incubated without substrate.
The relative activity of the enzymes studied was intense in the surface epithelium of the maxillo-turbinale and maxillary sinuses, and also pronounced in the apical part of the epithelial cells from other regions of the nasal cavity. The
subepithelial
glands showed moderate LDH and SDH activity with some regional differences. The olfactory mucosa also showed a high relative activity of the enzymes studied.
The intense staining activity of the three metabolic enzymes in the nasal and sinus mucosal epithelia and glands indicate a locally high oxidative enzyme capacity, due to high energy demands. Regional differences correspond to functional
differences as
well as to potentially functional metabolic demands. Regional differences correspond to functional differences as well as to potentially functional metabolic demands during pathophysiological conditions.
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