The experimental induction of ultrastructural damage in cardiac muscle

Experimentally-induced rises in intracellular calcium ([Ca2+]i) promote rapid myofilament degradation in amphibian and mammalian cardiac muscle strips. The relevance of these studies to the subcellular injury produced by ischaemia, the possible involvement of lysosomal enzymes and similarities with skeletal muscle are discussed.     

Glutaminase activity in rat skeletal muscle mitochondria

Summary Isolated rat skeletal muscle mitochondria took up about 40-ng-atoms O per min per mg protein, with glutamine as the only respiratory substrate. The mitochondria incubated in the presence of glutamine and KCN formed both ammonia and glutamate in equivalent amounts. The experiments reported here provide suggestive evidence that rat skeletal muscle mitochondria contain glutaminase (L-glutamine amidohydrolase EC 3.5.1.2.) activity.This work was supported by the Polish Academy of Sciences within the project II. 1, 2, 6.     

Glutaminase activity in rat skeletal muscle mitochondria

Isolated rat skeletal muscle mitochondria took up about 40-ng-atoms O per mg protein, with glutamine as the only respiratory substrate. The mitochondria incubated in the presence of glutamine and KCN formed both ammonia and glutamate in equivalent amounts. The experiments reported here provide suggestive evidence that rat skeletal muscle mitochondria contain glutaminase (L-glutamine amidohydrolase EC 3.5.1.2.) activity.     

Identification of type A monoamine oxidase in mouse and rabbit liver mitochondria

Summary Type A monoamine oxidase was identified in liver mitochondria of mouse and rabbit. 5-Hydroxytryptamine was a common substrate for type A and type B monoamine oxidase in these enzyme preparations where its concentration was 1.0 mM.     

Choline acetyltransferase and acetylcholinesterase in myo-tendinous and neuro-muscular junctions of mouse skeletal muscle

Zusammenfassung Topographischer Nachweis hoher Acetylcholinesterase-Aktivität an der Übergangsstelle Muskel/Sehne und, im Unterschied zur neuromuskulären Verbindung, an dieser Stelle kaum messbare Aktivität der Cholinacetyltransferase, was ohne Beziehung zur cholinergen Erregungsübertragung steht.     

Proteolytic capacity in mouse cardiac muscle following strenuous exercise

Summary Proteolytic capacity in mouse cardiac muscle was analyzed 1, 3, and 6 days after exhaustive intermittent or submaximal prolonged running. No significant changes were recorded in the activities of acid or alkaline proteases, -glucuronidase or trypsin inhibitor. Similarly, no changes were found in the rates of acid or neutral autolysis.Supported by grants (Nos 8840/78/77 and 8208/78/78) from the Ministry of Education and the Academy of Finland.     

Sarcosine dehydrogenase activity in liver mitochondria of infant and adult rats

Zusammenfassung Die Aktivität der Sarcosinedehydrogenase in Lebermitochondrien 7tägiger Ratten ist um 50% kleiner als in adulten Tieren. Dieser Unterschied ist nicht durch das Elektrontransportflavoprotein limitiert und kann auch nicht durch eine Änderung in dem relativen Wert der löslichen Proteine in den Mitochondrien erklärt werden.     

The ultrastructural localization of the G-6-P hydrolyzing enzyme activity in Kupffer cells

Zusammenfassung Die Aktivitätsverteilung eines Glukose-6-Phosphat hydrolysierenden Enzyms wurde in der Leber 24 Stunden alter Ratten elektronenmikroskopisch untersucht. Die Verteilung der Enzymaktivität in den Kupffer-Zellen schien mit der in den Hepatozyten gefundenen identisch zu sein.     

Functional state of mouse liver mitochondria in toxicoses due toAspergillus flavus andPenicillium rubrum

Zusammenfassung Es wurde die funktioneile Integrität der Mitochondrien nach Verunreinigung der Nahrung mitA. flavus undP. rubrum aus vergifteter Mäuseleber untersucht. Die Mitochondrienfunktion der mitP. rubrum vergifteten Leber ist in bezug auf ihre ATPase-Tätigkeit und oxydative Phosphorylierung gestört, während im mitA. flavus vergifteten Gewebe alle wichtigen Mitochondrienfunktionen unverändert blieben.     

Monoamine oxidase activity in rat erythrocytes: Evidence for its localization in reticulocyte mitochondria

Summary During growth of young rats, monoamine oxidase activity in erythrocyte membrane preparations decreases more rapidly than reticulocyte concentrations in the respective blood samples. Since reticulocytes lose their mitochondria prior to the substantia reticulo-filamentosa, the non-linear correlation between monoamine oxidase activity and reticulocyte counts indicates that erythrocyte monoamine oxidase is located in reticulocyte mitochondria.This work was supported by a grant from the Deutsche Forschungsgemeinschaft.     

Antioxidant activity of mouse liver and kidney extracts

Zusammenfassung Die hemmende Wirkung wässeriger Leber- und Nierenextrakte von Mäusen auf die DOPA-Auto-Oxydation wurde geprüft. Leber- und Nierenwerte waren von gleicher Grössenordnung und etwa dreimal grösser als die früher für Mäuse- und Menschenhaut bestimmten Werte. Der Hemmfaktor besteht zum grossen Teil aus Eiweiss und konnte in einen -SH-Gruppen enthaltenden, hitzeempfindlichen Teil und einen -SH-Gruppen-freien, hitzestabilen Teil getrennt werden. Die mögliche Bedeutung solcher Hemmstoffe für die Zelle wird erörtert.     

Ultrastructural localization of catalase and D-amino acid oxidase in 'normal' fetal mouse liver

In the hepatocytes of 'normal' fetal mice from mothers which were carriers of muscular dysgenesis, catalase and D-amino acid oxidase (DAAO) positive as well as negative peroxisomes were observed. DAAO reaction product was occasionally localized in patches around cell membranes and DAAO-positive peroxisomes were frequently observed near mitochondria.