title: Development of peroxisomes in amphibians. III. Study on liver, kidney, and intestine during thyroxine-induced metamorphosis.
abstract: This investigation was undertaken to study the ontogeny of hepatic, renal, and intestinal peroxisomes and/or microperoxisomes during thyroxine-induced anuran metamorphosis. Catalase activity was localized cytochemically after incubation in DAB medium, and studied biochemically by a spectrophotometric method. Our morphological and biochemical investigations suggest the formation of a new population of peroxisomes during the hormonal treatment. This is obvious especially for microperoxisomes of the intestinal epithelium since the larval tissue is completely replaced by a new layer during thyroxine-induced metamorphosis. For the peroxisomes of hepatocytes and kidney proximal tubule cells, our assumption is based on the following observations: 1) The number of peroxisomes increases in liver and kidney during thyroxine treatment; 2) this proliferation is accompanied by an enlargement of renal peroxisomes; and 3) 16 days after the beginning of the hormonal treatment, 5.4- and 2.4-fold increases are found for the specific activities of hepatic and renal catalase, respectively. A temporal coordination exists between the structure and the metabolism of peroxisomes and mitochondria during thyroxine-induced metamorphosis.
mesh_terms: D000818:Animals; D001001:Anura / Q000033:anatomy & histology; D002374:Catalase / Q000378:metabolism; D007422:Intestines / Q000201:enzymology / Q000648:ultrastructure*; D007668:Kidney / Q000201:enzymology / Q000648:ultrastructure*; D008099:Liver / Q000201:enzymology / Q000648:ultrastructure*; D008675:Metamorphosis, Biological / Q000187:drug effects*; D008830:Microbodies / Q000187:drug effects* / Q000648:ultrastructure; D011892:Rana catesbeiana / Q000033:anatomy & histology*; D013974:Thyroxine / Q000494:pharmacology*
chemical_list: D002374:Catalase; D013974:Thyroxine