Peroxisomes are ubiquitous organelles containing enzyme sequences for beta oxidation of fatty acids, synthesis of bile acids, and ether phospholipids. In the inherited peroxisomal diseases one or more enzymes are deficient in hepatic, renal, and fibroblast peroxisomes. We have examined peroxisomes by light and electron microscopy in 29 duodenal biopsy specimens (21 with normal mucosa) after staining for catalase activity, a marker enzyme. Peroxisomes were most numerous in the apices of the nucleus and at the villus base. Two types were distinguished: rounded to oval forms with a median lesser diameter of 0.23-0.31 microns, and tubular, vermiform organelles 0.1 microns thick and up to 3 microns long. Both types coexist in most patients. Tilting of sections and examination of semithin sections at 120 kV did not show connections between individual organelles. By morphometry, volume density was at least 0.45-0.62% of cellular volume, compared to 1.05% in human liver. In contrast, in four out of five individuals surface density of the peroxisomal membrane was 1.4-2.3 times higher than in control livers; this is expected to favour the exchange of metabolites. We suggest that intestinal peroxisomes contribute substantially to the breakdown of very long chain fatty acids.
Statistics from Altmetric.com
If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.