Effects of starvation and a carbohydrate-rich diet on glycogen metabolism in a gastropod mollusc,Megalobulimus oblongus

• 1.1. Administration of a carbohydrate-rich diet increased haemolymph glucose levels and glycogen concentration in hepatopancreas, mantle and muscle.
• 2.2. Glycogen concentration in tissues decreases after 2 weeks of starvation and haemolymph glucose levels did not change significantly.
• 3.3. However, starvation did not induce a decrease in the intrinsic synthetic capacity in tissues.
• 4.4. Glycogen synthesis in tissues from animals fed with lettuce or a carbohydrate-rich diet, increases with increasing glucose concentration in the media.
• 5.5. However, in mantle slices from snails adapted on a carbohydrate-rich diet, the glycogen synthetic capacity was lower than in slices from snails fed with lettuce.

     

1H NMR study of metabolic alterations in the small intestine of rats infected with Hymenolepis diminuta

• 1.1. 1H NMR spectra of the duodenum, jejunum and ileum tissues of the small intestine of a rat showed metabolic gradients.
• 2.2. The concentrations of metabolites in these gut regions were altered by the presence of the tapeworm Hymenolepis diminuta.
• 3.3. In the infected duodenum there was significantly less glycogen, glucose and phosphocreatine/creatine, but significantly more lactate than in the corresponding controls.
• 4.4. Infected jejunum contained significantly less betaine but significantly more succinate, alanine and lactate.
• 5.5. Infected ileum had significantly less glycogen and taurine but significantly more alanine and lactate.

     

Identification of the major annexins in Ehrlich ascites tumor cells

• 1.1. Three calcium-binding proteins have been purified from Ehrlich ascites tumor cells.
• 2.2. They were identified by amino acid sequence analysis on selected fragments obtained by tryptic digestion.
• 3.3. The proteins belong to the annexin family and were identified as annexins II, III and V.
• 4.4. Antibodies raised against the proteins were used to examine for their presence in a number of murine tissues.
• 5.5. The occurrence was found to be in reasonable accordance with earlier reports.

     

Effect of hibernation on liver and kidney metabolism in 13-lined ground squirrels

• 1.1. Metabolic rates and adenine nucleotide content of liver and kidney from hibernating ground squirrels were measured and compared to rats to study the biochemical adaptation to hibernation.
• 2.2. High rates of renal and hepatic gluconeogenesis were observed in squirrels, particularly from propionate and glycerol compared to rat.
• 3.3. During hibernation and starvation soluble phosphoenolpyruvate carboxykinase activity was increased in both liver and kidney.
• 4.4. Although metabolic rates are decreased during hibernation the results suggest that the enzymic complement is maintained at high activity even during torpor.

     

A comparative study of the basic nuclear proteins from sperm of bivalve molluscs

• 1.1. Basic nuclear proteins from spermatozoa of the three mollusc species belonging to the class Bivalvia have been analyzed using one- and two-dimensional electrophoresis.
• 2.2. Four nuclear basic proteins have been purified and their amino acid compositions determined.
• 3.3. In these spermatozoa histone-type proteins coexist with protamine-like proteins.
• 4.4. The protamine-like proteins that have been studied show different electrophoretic behavior but in general are similar, with a high content of lysine, arginine, alanine and serine.
• 5.5. Interspecific variability has been found for the H1-like histone.

     

Effects of salinity and temperature on oxygen consumption in a freshwater population of Palaemonetes antennarius (Crustacea,decapoda)

• 1.1. After step-like increases in salinity the shrimps exhibit the smallest increase in oxygen consumption in the lower salinity range. At higher salinities the shrimps show longer recovery times and greater increases in the metabolic rate after salinity shock.
• 2.2. In steady-state experiments, the shrimps display the lowest oxygen consumption rates near the isosmotic point. The lowest metabolic rates occur at salinities of 3‰ and 10‰ At salinities of 20‰ and above the rate of metabolism increases by 20–30%.
• 3.3. The calculated osmoregulatory work for animals in fresh water amounts to only 2.7% of routine metabolism and drops to 1.1% for shrimps in 3‰ and 0.7% in 5‰ salinity.
• 4.4. Locomotory activity in the form of position change was not responsible for the increased oxygen consumption of the animals after salinity shocks. A “tentative swimming activity” by fast and frequent beating of the pleopods without position change may be an important factor in the increase of metabolic rates.
• 5.5. In its temperature response, the brackish water population has a higher metabolic rate than the freshwater one. Between 5 and 35°C Q ₁₀-values range from 4.01 to 1.37.

     

The yolk polypeptides of a free-living rhabditid nematode

• 1.1. The yolk proteins of hermaphrodite Dolichorhabditis sp. (Nematode, Rhabditida) are composed of at least three polypeptides: VT1, VT2 and VT3 with molecular masses of 175.2, 107 and 82 kDa respectively.
• 2.2. All three yolk polypeptides make up at least one native protein complex which can be resolved by PAGE.
• 3.3. The yolk proteins are glycosylated and can be isolated by chromatography in Con A-Sepharose.
• 4.4. Partial chymotryptic hydrolysis shows that VT2 in different from its C. elegans homologue, YP115.
• 5.5. The main polypeptides synthesized by whole animals are the yolk components which are actively secreted in the incubation medium.

     

Metabolic rates of Calathus melanocephalus (L.) (coleoptera,carabidae) from alpine and lowland habitats (jeløy and finse,norway and drenthe,the netherlands)

• 1.1. Metabolic rates (ml O₂/mg/hr) of three geographically separated populations of the carabid beetle Calathus melanocephalus L. (Finse and Je 10y, Norway and Drenthe, The Netherlands) were measured and compared by ANCOVA.
• 2.2. No significant relationship (P > 0.05) between metabolic rates and body weight or sex of the animals were found.
• 3.3. Individuals mostly acclimated to low temperatures by increased metabolic rates and in the opposite direction to higher temperatures. Individuals collected in early summer also showed higher metabolic rates than those caught later in the autumn.
• 4.4. Contradicting the theory of metabolic cold adaptation, beetles from The Netherlands had the highest metabolic rates, beetles from Finse intermediate rates and beetles from Jeløy the lowest rates.
• 5.5. No significant relation were found between geographical origin of the beetles and their respective chill-coma temperature.

     

Haematology of the australian eastern quoll,Dasyurus viverrinus

• 1.1. A variety of haematological parameters were determined in adult Dasyurus viverrinus.
• 2.2. Haemoglobin and red cell counts were high with a very low mean cell volume.
• 3.3. Basophils are absent but the eosinophils contain small numbers of basophilic granules which may indicate a dual role for this cell.
• 4.4. “Ring Form” leucocytes are present.
• 5.5. Three types of red cell picture could be identified, some animals showing large numbers of spherocytes, spicule cells, and inclusion bodies.
• 6.6. These cells resemble those found in some inherited human haemolytic anaemias but there was no evidence of haemolysis in the animals.
• 7.7. An alkali resistant haemoglobin component is present.

     

Specific dynamic action (SDA) in the supralittoral isopod,Ligia pallasii: Identification of components of apparent SDA and effects of dietary amino acid quality and content on SDA

• 1.1. Specific Dynamic Action (SDA) effects of diet were investigated in the supralittoral isopod, Ligia pallasii, using defined chemical diets.
• 2.2. “Apparent SDA”, or the total rise in metabolic rate following a meal, was resolved in animals eating a nutritionally complete chemical diet into three components: 8% mechanical costs of moving food through the gut, 40% “excitement costs” due to investigator disturbance and presence of food, and 52% SDA.
• 3.3. Excitement costs in animals exposed to food but which chose not to eat showed non-significant variation between diets containing different levels of chemical nutrients, but were significantly less on a diet containing only cellulose and agar.
• 4.4. SDA increased with increasing concentration of amino acids in the diet.
• 5.5. Substitution of whole-protein casein for free amino acids in the diet had no significant SDA effect, while substitution of free amino acids in the ratio found in casein more than doubled the SDA effect.
• 6.6. Deletion of alanine from the diet caused no significant effect on SDA, while deletion of phenylalanine caused a highly significant elevation in SDA.

     

Possible involvement of adenylylation in the modification of a 26 kDa protein in rat parotid acinar cells

• 1.1. Adenylylation, a posttranslational modification of proteins, was investigated in saponin-permeabilized acinar cells of the rat parotid gland.
• 2.2. When cells were incubated with [2,8-³H]ATP, several proteins, including a 26 kDa protein in the particulate fraction, were labeled.
• 3.3. Upon incubation of cells with [α-³²P]ATP in the presence of cAMP and 3-isobutyl-lmethylxanthine, ³²P-labeling of the 26 kDa protein was observed.
• 4.4. After treatment with snake venom phosphodiesterase, [³²P]AMP was released from the 26kDa protein. Such release was not observed when cells were labeled with [γ-³²P]ATP.
• 5.5. The ³²P-labeling pattern of proteins with [α-³²P]ATP was clearly different from that with [adenylate-³²P]NAD⁺.
• 6.6. The results suggest that the 26 kDa protein is one of the adenylylation substrates in rat parotid acinar cells.

     

Proteolysis of skeletal muscle in yellowfin tuna (Thunnus albacares): Evidence of calpain activation

• 1.1. White muscle of yellowfin tuna is subject to a form of deterioration known as “burnt tuna”.
• 2.2. TEM and SDS-PAGE were used to quantify cellular differences in deteriorated white muscle of yellowfin tuna.
• 3.3. Electron micrographs showed a significant loss of Z-disc integrity and an increase in intracellular edema in burnt tuna.
• 4.4. Electrophoresis established that a specific doublet of proteins, 42 kD and 46 kD was lost.
• 5.5. Proteolysis of isolated myofibrils incubated in calpain (EC 3.4.22.17) was greatest at pH 7.5 and was selective for intermediate molecular weight proteins.
• 6.6. This evidence suggests that burnt tuna is a specific and limited proteolysis of myofibrillar structural proteins characteristic of calpain proteolysis.

     

NAD(P)H dehydrogenase from rabbit and rat liver: Purification and some properties

• 1.1. NAD(P)H dehydrogenase from rabbit liver was purified to electrophoretic homogeneity using a procedure also found applicable for the rat liver enzyme.
• 2.2. Rabbit and rat liver enzymes showed different behaviour in isoelectric focusing and different K_m values and turnover numbers.
• 3.3. Both enzymes were inhibited to similar extents by warfarin.
• 4.4. The rabbit enzyme is composed of two subunits of mol. wt 27,000 and contained 1 FAD group per subunit.
• 5.5. Some absorption and circular dichroism properties of the rat enzyme are shown.

     

Correlation of acid phosphatase but not alkaline phosphatase activity with myelination in the developing mouse brain

• 1.1. Neonatal mice received subcutaneous injections of buffer, thiourea (TU) or propylthiouracil (PTU).
• 2.2. The PTU-treated mice were sacrificed on postnatal day 14 (P14) and the TU-treated mice on P28.
• 3.3. Brain weights of the TU- and PTU-treated mice were not significantly different from the controls.
• 4.4. Acid but not alkaline phosphatase activity in the braistem decreased after TU and PTU treatment.
• 5.5. Myelination as indicated by intensity of luxol fast blue staining was weaker in drug-treated animals.
• 6.6. The level of myelin marker enzyme, 2′,3′-cyclic nucleotide 3′-phosphohydrolase, was lower in the brainstem of PTU-treated animals.
• 7.7. The results suggest a correlation between acid phosphatase but not alkaline phosphatase activity with myelination in the developing mouse brain.

     

Long-term starvation in Xenopus laevis daudin—III. Effects on enzymes in several tissues

• 1.1. Adult, female Xenopus laevis were subjected to 12 months of starvation.
• 2.2. Starvation resulted in a continuous reduction in the activity of both hepatic and renal glucose-6-phosphate dehydroganse.
• 3.3. Fructose-1,6-diphosphatase was significantly reduced at months 10 and 12 in the liver, and at months 4, 10, and 12 in the kidney.
• 4.4. Pyruvate kinase activity of muscle and liver decreased during the experimental period whereas the renal enzyme remained essentially unchanged.
• 5.5. Both hepatic and renal glutamate-pyruvate transaminase (GPT) and hepatic glutamate-oxaloacetate transaminase (GOT) showed a reduction of activity after 2 and 4 months of starvation followed by an increase in GPT but not in GOT.

     

Variability of histone H1 in rabbit populations

• 1.1. Perchloric acid-soluble proteins containing H1 histone as a main component were isolated from whole liver, lung and kidney of New Zealand White, Chinchilla, French Silver and Czech Spotted rabbits.
• 2.2. Proteins were resolved in a two-dimensional polyacrylamide slab gel into 4–5 spots depending on the tissue.
• 3.3. One of the histone subtypes, Hle, was found to be nonuniformly distributed within rabbit populations.
• 4.4. The prevailing fraction of animals had only a single spot of H1e (phenotype A). Approximately 10–28% of animals, depending on the breed, had two spots of H1e (e₁ and e₂; phenotype B) that slightly differed in the apparent molecular weights.
• 5.5. These two distinct gel patterns of H1e showed no tissue specificity, and the same phenotype was revealed in all tissues from the same animal.

     

Effects of the nonsteroidal anti-inflammatory drug piroxicam on energy metabolism in the perfused rat liver

• 1.1. The actions of piroxicam, a nonsteroidal and noncarboxylic anti-inflammatory drug, on the metabolism of the isolated perfused rat liver were investigated. The main purpose was to verify if piroxicam is also active on glycogenolysis and energy metabolism, as demonstrated for several carboxylic nonsteroidal anti-inflammatories.
• 2.2. Piroxicam increased oxygen consumption in livers from both fed and fasted rats.
• 3.3. Piroxicam increased glucose release and glycolysis from endogenous glycogen (glycogenolysis).
• 4.4. Gluconeogenesis from lactate plus pyruvate was inhibited.
• 5.5. The action of piroxicam on oxygen consumption was blocked by antimycin A, but not by atractyloside.
• 6.6. The action of piroxicam in the perfused rat liver metabolism seems to be a consequence of its action on mitochondria.
• 7.7. It can be concluded that inhibition of energy metabolism and stimulation of glycogenolysis are not specific properties of carboxylic nonsteroidal anti-inflammatory drugs.

     

Comparative aspects of iodine conservation in mammals

• 1.1. Comparative aspects of iodine conservation in mammals were studied on the basis of published data on kidney and thyroid weights and function.
• 2.2. Very small mammals possessed an efficient reabsorption of iodide to compensate for the high glomerular nitration rate (GFR).
• 3.3. Humans and mammals of a similar and larger size had “lost” the ability to reabsorb iodide efficiently.
• 4.4. Very large mammals are protected against renal loss of iodide due to the relatively low GFR.
• 5.5. Thyroid weights in relation to body weight were highest in humans suggesting that humans and other mammals of a similar size are especially susceptible to iodine deficiency.

     

Role of the visceral nerve in heart rate variations during different behavioral patterns in Megalobulimus sanctipauli (mollusca,gastropoda, pulmonata)

• 1.1. The role of the visceral nerve in mediating the changes in heart rate associated with different behavioral patterns was investigated in Megalobulimus sanctipauli.
• 2.2. The results of acute and chronic denervation experiments indicate that the visceral nerve has no excitatory or inhibitory tonic action on the heart of snails retracted into the shell, nor does it account for the increase in heart rate associated with the locomotion and feeding behaviors.
• 3.3. These changes in heart rate are, probably, indirect effects of increased activity such as an increase in venous return.
• 4.4. The visceral nerve is responsible for approximately 3/4 of the increase in heart rate associated with the first minute of extrusion.
• 5.5. The small increase in heart rate observed in denervated animals is probably caused by an increase in venous return generated by muscle activity that forces the head and food out of the shell.

     

l-Leucine intestinal transport at different ages in chicken: Effect of anticoccidial drugs

• 1.1. l-Leucine transport by everted slices of duodenum, jejunum ileum and cecum of 1-, 2- and 3-week-old chickens has been determined.
• 2.2. The effects of the administration with the diet of three anticoccidial drugs: monensin, maduromicin ammonium and nicarbazine have been studied.
• 3.3. In the control animals, there is a reduction on intestinal transport with age, except in the duodenum which is not age-dependent.
• 4.4. Momensine induces an increase on leucine transport in the duodenum and cecum at all ages studied and only in the 3-week-old animals in the jejunum and ileum.
• 5.5. Nicarbazine reduces jejunal absorption of leucine and does not affect the function of the other segments.
• 6.6. Maduromicin ammonium has almost no effect on the absorptive process.