Václav Kubišta

Flavones inHelix pomatia L.

In verschiedenen Organen der Weinbergschnecke sind Flavonfarbstoffe chemisch nachgewiesen und histochemisch lokalisiert worden.

The presence of riboflavin in the luminous material of the earthworm Eisenia submontana.

In den Lymphozyten derEisenia submontana ist ein Leuchtmaterial vorhanden, das Riboflavin enthält. Mit Hilfe der Papierchromatographie konnte nachgewiesen werden, daß Riboflavin hier als solches, nicht aber als Flavinphosphat oder als Flavin-adenin-dinukleotid vorliegt.

Heterogeneity of insect flight muscle mitochondria as demonstrated by different phospholipid turnover in vivo

Abstract Homogenates of the flight muscle of Periplaneta americana were separated by differential centrifugation into several fractions. Examination by electron microscopy indicated that two of these fractions contain predominantly intact mitochondria. When expressed relative to the protein content they have a high content of diphosphatidylglycerol and their phospholipids incorporate [ 32 P]-orthophosphate in vivo much more slowly than phospholipids in the supernatant. The mitochondria sedimenting at the lower speed have, in vivo , a significantly lower incorporation or radioactive phosphate into diphosphatidylglycerol and phosphatidylethanolamine than those of the lighter fraction. From developing muscle, fractions of similar composition and yield can be obtained, but they do not differ in the rate of incorporation of radioactive phosphate into diphosphatidylglycerol in vivo .

Phospholipid metabolism in red and white insect muscle

The red flight musculature of Schistocerca gregaria contains twice as much phospholipids than the white femoral musculature. In individual phospholipids the difference is greatest in phosphatidylethanolamine and phosphatidylglycerol, lowest in sphingomyeline and phosphatidylinositol. The plasmalogen content is very low. After an injection of 32P orthophosphate the increase of specific activity during six days follows a similar course in both muscle types in phosphatidylethanolamine, sphingomyeline and phosphatidylserine but is more rapid in red than in white muscle in phosphatidylcholine (1.3 ×) and in phosphatidylinositol (5 ×). The incorporation into diphosphatidylglycerol is extremely slow. Flight induces an increase in the specific activity in phosphatidylinositol.

Differential effect of anaerobiosis on phospholipid metabolism in insect muscle

Abstract An in vivo anaerobic exposure of 80 min duration induces little change in the rate of incorporation of 32 P into flight muscle phospholipids of male American cockroaches taken 1–3 days after adult ecdysis. In mature animals (1–3 months after adult ecdysis) the incorporation rate is strongly depressed, phosphatidylcholine and phosphatidylethanolamine being distinctly more affected than phosphatidylinositol. During 60 min recovery from anaerobiosis only phosphatidylinositol reaches the specific radioactivity found in control muscles. In phosphatidylcholine and phosphatidylethanolamine not even the control rate of labelling is attained during this period. The results are discussed.

Anaerobic formation of alanine in the metathoracic musculature of Periplaneta americana

In the isolated metathoracic muscles of Periplaneta americana alanine content increased in anaerobiosis; its increase corresponded to approximately one-quarter of the glycogen consumed. Labelling of glycogen in vivo, by injecting radioactive glucose, resulted in a considerable labelling of alanine as well, therefore no convincing evidence for alanine formation from glycogen was obtained in intact muscle. Homogenates of thoracic muscles also formed alanine anaerobically; by adding radioactive glycogen as substrate all the alanine could be demonstrated to originate from glycogen.

The effect of isoprenaline on the phospholipid content of the compact and spongious musculature of the carp ventricular myocardium

1. After a single injection of 40 mg kg-1 of isoprenaline to the carp, lysophospholipids appear in the tissue of the heart ventricle, ethanolamine plasmalogens increase and choline plasmalogens decrease; phosphatidylinositol is lowered in the spongious layer only. 2. Daily administration of 5 mg kg-1 of the drug leads, after 5 doses, to a dramatic decrease of the diphosphatidylglycerol content; during the subsequent 5 and 10 doses a return to normal values occurs. Shifts in plasmalogens are similar to those found after a single high dose. Some other phospholipids change significantly. 3. All changes reveal that the spongious musculature is more sensitive to the drug than the compact one.

Increased phospholipid turnover in denervated insect muscle

Abstract 1. 1. Phospholipid metabolism was studied by [32P]-orthophosphate incorporation in vivo in unilaterally denervated metathoracic muscles of adult male cockroaches (Periplaneta americana) 14 days after denervation. 2. 2. No change in the wet weight or in the labelling rate of tissue inorganic phosphate and phosphoarginine was found. 3. 3. There was a slight decrease in the dry weight and phospholipid content in denervated muscle. 4. 4. There was an increase in the labelling rate of phospholipids in the denervated muscles ranging from 161% in phosphatidyl choline to 247% in diphosphatidyl glycerol. This increase was similar in three subcellular fractions examined.

Changes in the phospholipid content in the left heart ventricle of male mice during repeated administration of isoprenaline

1. Male mice were injected 5 mg/kg isoprenaline (IPRO) daily and the heart weight, dry weight and phospholipid content in the left ventricle determined 24 hr after the last injection on days 1, 3, 5 and 10. 2. The phospholipid content sinks during the experiment, but the onset of the change is different in different phospholipids: for diphosphatidylglycerol it is clearly significant after 3 days, for phosphatidylcholine and phosphatidylethanolamine after 5 days and for sphingomyelin after 10 days; the relative amplitude of the change in this latter phospholipid was greatest of all. 3. If IPRO is given for 3 days and physiological saline for next 7 days, the content of some phospholipids (PE, SM and PG) continued to decrease. This suggests an important delayed effect of IPRO action.

Effect of early denervation on the phospholipid metabolism of insect flight muscle

Abstract 1. 1. Metathoracic muscles of Periplaneta americana males denervated immediately after adult ecdysis and examined 16 days later for phosphate and phospholipid metabolism were found to retain some but not all characteristics of the immature muscle. 2. 2. Like in immature muscle the penetration of labelled phosphate into the muscle and the level of specific radioactivity attained by phosphoarginine is higher than in normal muscle. 3. 3. Denervation prevents the increase in the tissue level of most phospholipids normally occurring during maturation. 4. 4. Denervation preserves the higher rate of 32 P incorporation characteristic for immature muscle in all phospholipids except diphosphatidylglycerol.