Adenylate energy charge: A possible trophic index for management of oyster intensive aquaculture

• 1.1. O. edulis and C. gigas both exhibit a seasonal variation in AEC with minimum values in summer. Two factors, food and temperature, were examined to explain these low summer values.
• 2.2. The AEC level varied with food level but a seasonal pattern was still observed. Two age groups of oysters were tested, giving a similar response.
• 3.3. The effect of temperature on the seasonal variations in AEC was confirmed by a significant correlation between AEC and temperature. This relationship allows us to calculate an AEC standard that only retains the trophic information.
• 4.4. Different trophic levels were identified in Marennes-Oléron Bay with AEC standard but growth rate was not related to them. So, AEC may inform on the carrying capacity of a given area but does not predict growth performances which will depend on other parameters.

     

Relationship between brain trehalase activity and trehalosema during direct and diapausing development in Pieris brassicae

• 1.1. Brain trehalase specific activity and trehalosemia were measured during the end of the developmental life cycle in non-diapausing and diapausing insects.
• 2.2. During non-diapausing development, trehalosemia reached maximum values at the beginning of pupal life. Then a constant decrease was observed up to the end of adult life.
• 3.3. The specific activity of brain trehalase was maximum when the insects were in active feeding periods, minimum activity appearing during moulting phases.
• 4.4. During diapausing development, trehalosemia was very high at the beginning of pupal life, particularly when insects were exposed to wintering conditions.
• 5.5. When diapause was broken, trehalosemia fell, announcing adult emergence.
• 6.6. Brain trehalase activity showed the same qualitative variations as in non-diapausing larvae, but with rather lower values.
• 7.7. During pupal life, brain trehalase activity decreased markedly during the long period necessary to obtain diapause breakdown.
• 8.8. Wintering conditions allow a progressive increase of brain trehalase activity, which preceded the fall of trehalosemia.

     

Organ specific changes in energy metabolism due to anaerobiosis in the sea mussel Mytilus edulis (L.)

• 1.1. Anaerobic energy metabolism was investigated in different organs of Mytilus edulis and the whole animal.
• 2.2. Succinate accumulates to high levels in most organs but remains low in the hemolymph.
• 3.3. After 16 hours propionate accumulation is observed in all organs. Experimental evidence is not sufficient yet to point out organs that produce more propionate than others.
• 4.4. Acetate is a minor end product.
• 5.5. Acetate and propionate are found in the hemolymph in amounts equal to those in the organs.
• 6.6. Animals incubated in oxygen-free seawater accumulate more end products than animals exposed to air, in the form of volatile fatty acids that are excreted into the incubation water.
• 7.7. Alanine and glutamine increase in the posterior adductor muscle. Aspartate decreases in the total animal, posterior adductor muscle and gills, while in the hemolymph decrease in alanine, asparagine, serine, threonine and proline are observed.

     

Seasonal changes of total lipids in the turtle Sternotherus odoratus

• 1.1. Seasonal variation in total lipids was examined in several body components of the turtle Sternotherus odoratus.
• 2.2. Carcass fat stores in both sexes were depleted during winter. Additionally, a decline in carcass lipids was associated with increases in gonadal mass.
• 3.3. Concentrations of liver lipids were maximal during August and minimal during winter.
• 4.4. Males showed little seasonal change in plasma lipid levels, whereas females had seasonal peaks temporally associated with ovarian development and carcass fat storage.
• 5.5. Ovarian concentrations of lipids were minimal after nesting and increased during fall.
• 6.6. Results suggest that S. odoratus uses stored fats both for reproduction and maintenance during winter.

     

Variation of l-gulonolactone oxidase activity in placental mammals

• 1.1. The activity of l-gulonolactone oxidase (EC 1.1.3.8) in livers of 49 species of eutherian mammals varied intraspecifically among individuals; coefficients of variation were 0.2 to 0.4 in many species.
• 2.2. Differences observed in l-gulonolactone oxidase activity among strains of laboratory rats and domestic rabbits are probably genetically controlled.
• 3.3. Pronounced sex differences in l-gulonolactone oxidase activity were found in some species, particularly in the genera Peromyscus, Reithrodontomys and Onychomys.
• 4.4. Mormota monax exhibited seasonal variation in l-gulonolactone oxidase somewhat like that previously observed in Sylvilagus floridanus; no such seasonal variation was found in Sciurus carolinensis.
• 5.5. Hibernation did not affect l-gulonolactone oxidase activity in Spermophilus tridecemlineatus.
• 6.6. In four species of rodents, Microtus ochrogaster, Tylomys panamensis, Octodon degus and Sigmodon hispidus, l-gulonolactone oxidase activity was not affected by the level of dietary ascorbate.

     

Effect of developmental derangements on the proteolytic and protease-inhibitory activities in Galleria mellonella (Insecta)

• 1.1. Protease inhibitory activity in the whole body homogenates of Galleria mellonella larvae exhibits maxima at the beginning of the last larval and pupal instars. Injury, chilling, immobilization, and ligations of larvae cause an increase of inhibition.
• 2.2. The inhibitory activity is high in the haemolymph but low in midgut and faty body. By contrast, the proteolytic activity is low in haemolymph and high in both midgut and fat body.
• 3.3. Starvation and ligations cause a dramatic fall of the proteolytic activity and increase of the inhibitory activity in examined organs.

     

δ-Aminolevulinic acid dehydratase inactivation by uroporphyrin I in light and darkness

• 1.1. The action of uroporphyrin I on erythrocytic ALA-D activity under dark and light conditions was examined.
• 2.2. Photo and non-photoinactivation of ALA-D induced by uroporphyrin I were observed.
• 3.3. Both effects were dependent on uroporphyrin concentration, temperature and time of exposure of the protein to the porphyrin.
• 4.4. Light-dependent effect of uroporphyrin I is related with the phototoxicity of porphyrins and could be produced by primary amino acid photooxidation followed by secondary cross-linking of the protein.
• 5.5. Light-dependent effect of uroporphyrin I could be ascribed to a direct enzyme inhibition due to binding of the porphyrin to the protein inducing structural changes at or near its active site.

     

Seasonal effects of prolactin on aspects of carbohydrate and lipid metabolism in the goldfish,Carassius auratus

• 1.1. Diurnal and seasonal variations of certain aspects of carbohydrate and lipid metabolism to ovine prolactin (PRL) treatment in the goldfish, Carassius auratus, were examined.
• 2.2. PRL treatment late in the light phase of a long photoperiod during spring depletes liver glycogen stores. During fall liver glycogen levels are not affected by PRL treatment in fishes acclimated to long or short photoperiods. PRL is hypoglycaemic in fall and spring.
• 3.3. PRL administered late in the light phase of a long photoperiod during spring increases plasma and liver total lipids and plasma cholesterol, while decreasing plasma triglycerides. In fall PRL may increase or decrease plasma organic-bound P levels dependent upon injection time.

     

Unsaponifiable matter of liver oil of intensively reared sea bass (Dicentrarchus labrax): Sterols and aliphatic alcohols

• 1.1. Sterols and aliphatic alcohols of sea bass (Dicentrarchus labrax) liver oil intensively reared and fed on three different diets were studied, with the aim of verifying any differences due to diets and seasonal variations.
• 2.2. Ten components of the sterol fraction were found; the largest component was cholesterol.
• 3.3. Nineteen linear chain alcohol components were identified: there were between 14 and 32 carbon atoms, mainly saturated; the 28:0 and the 30:0 were the most abundant.
• 4.4. Evident differences were not due to the three diets adopted, but to the seasonal conditions; the quantity of sterols present in the liver decreased in the cold months, in connection with reproduction.

     

Seasonal variations in the anaerobic metabolism of the mussel Mytilus edulis (L.)

• 1.1. The incorporation of atmospheric ¹⁴CO₂ into the ethanol soluble metabolites of the tissues of the mussel, Mytilus edulis, exposed to the atmosphere, was measured monthly between July 1976 and June 1977.
• 2.2. The total incorporation of ¹⁴CO₂ was found to be greater in the summer than in the winter and these seasonal effects were not temperature-dependent.
• 3.3. The incorporation of ¹⁴CO₂ into the individual metabolites is discussed in relation to possible seasonal variations in the operation of the anaerobic succinate pathway and seasonal variations of tissue glycogen concentrations.

     

Steroid synthesizing capacity of the dorsal body of Helix pomatia L. (Gastropoda)—an in vitro study

• 1.1. In vitro studies demonstrated the presence of the enzyme 3β-hydroxysteroid dehydrogenase (3β-HSD) in the dorsal body complex, ovotestis and buccal ganglia of Helix pomatia.
• 2.2. Results of incubations with tritiated pregnenolone and tritiated dehydroepiandrosterone indicate substrate specificity of the 3β-hydroxysteroid dehydrogenase.
• 3.3. The activity of the two 3β-hydroxysteroid dehydrogenases vary independently of each other during different physiological states of the animal.
• 4.4. Before oviposition the conversion of dehydroepiandrosterone into androstenedione in all tissues investigated exceeds that of pregnenolone into progesterone. On the contrary, after oviposition this is reversed for the ovotestis.
• 5.5. The relative importance of the pathways in steroidogenesis followed in the organs studied is discussed.

     

Na+-K+ ATPase and carbonic anhydrase activities in larvae,postlarvae and adults of the shrimp Penaeus japonicus (Decapoda,Penaeidea)

• 1.1. Activities of Na⁺-K⁺ ATPase and carbonic anhydrase were measured through the early post-embryonic development of Penaeusjaponicus. In adults, only the Na⁺-K⁺ ATPase activity was measured.
• 2.2. ATPase activity was variable in the successive development stages. From zero in nauplii, the activity slightly increased in zoeae, and rose sharply in mysis stages 2 and 3.
• 3.3. A further significant increase in activity was noted at the transition from late mysis to early postlarvae, concomitant with a change from the larval osmoconforming pattern of osmoregulation to the postlarval and adult hyper-hyporegulating pattern.
• 4.4. The activity of Na⁺-K⁺ ATPase, measured in isolated cephalothorax, increased from PL3 to PL4 to its maximum value in PL5; at this stage, osmoregulatory capacity was fully efficient.
• 5.5. In young stages of P. japonicus, the variations in Na⁺-K⁺ ATPase activity appear correlated with the development of osmoregulatory ultrastructures, and with osmoregulation and salinity tolerance.
• 6.6. These results are discussed with regard to their ecological and physiological implications.
• 7.7. In adults, the activity of Na⁺-K⁺ ATPase was high in gills and epipodites and no activity was detected in branchiostegites. These results are related to the ultrastructure of these organs.
• 8.8. The activity of carbonic anhydrase did not change significantly in larval and postlarval stages.
• 9.9. From these results, it is proposed that the effector sites of osmoregulation are located in branchiostegites, pleurae and epipodites in postlarvae, and in epipodites and mainly in gills in adults.

     

Initial characterization of human thymocyte sialidase activity: Evidence that this enzymatic system is not altered during the course of T-cell maturation

• 1.1. The sialidase activity of human thymocyte was examined by a fluorogenic assay.
• 2.2. These studies revealed that human thymocyte sialidase activity is essentially acid-active and membrane-bound since 59.6% and 33% of the total activity was recovered in the lysosome-enriched and microsomal fractions, respectively.
• 3.3. A weak activity was also detected in the cytosolic fraction.
• 4.4. However, the acidic optimum pH of this soluble sialidase was at variance with the general concept of mammalian soluble sialidases which are known to be optimally active at more neutral pH.
• 5.5. This acidic soluble sialidase seems to be a general characteristic of the human T-cell lineage since examination of mature circulating T-cells revealed that they contain a soluble sialidase activity similar to that observed in thymocytes.
• 6.6. Analysis of mature and immature thymocyte subpopulation obtained by differential PNA agglutination indicated that this enzymatic system was not altered during the course of thymic maturation.
• 7.7. These results suggest that unlike in T-cell activation where changes in the level of sialidase activity were shown to influence the extent of cell surface sialylation and thereby the cell physiology, this enzymatic system seems not to be involved in the fluctuation of cell surface sialic acid content observed during thymic maturation.

     

Seasonal variation in the energy metabolism in an estuarine crab,Chasmagnathus granulata (Dana, 1851)

• 1.1. The effects of seasonal variation on the carbohydrate and lipid metabolism of the Chasmagnathus granulata were investigated.
• 2.2. Glycemia is high in winter and summer and low in spring and fall.
• 3.3. The glycogen content in the hepatopancreas and muscle is higher in fall and winter, and decreases during spring and summer.
• 4.4. The muscle lipids are higher in summer, and decrease during fall and winter whereas hepatopancreas lipids are higher except in the fall.
• 5.5. The crabs show change in the metabolic pattern of lipids and carbohydrates during the seasons of the year.

     

Comparative study on AMP deaminase in gill,muscle and blood of fish

• 1.1. High AMP deaminase activities were determined in the gill of one selachian, Scyliorhinus caniculus, and five teleosts, Anguilla anguilla, Cyprinus carpio, Salmo gairdneri, Perca fluviatilis and Esox lucius.
• 2.2. The highest activity was generally found in skeletal white muscle, except in A. anguilla and S. caniculus.
• 3.3. In s. caniculus a very high AMP deaminase activity was found in the blood where it was shown to be tightly regulated by inorganic phosphate.
• 4.4. Seasonal variations were observed for AMP deaminase activity in gill and white muscle, but also for blood Hb and protein concentration in the three tissues examined.

     

Proteolysis post mortem in North Atlantic krill

• 1.1. The autoproteolytic processes in selected species of North Atlantic krill, Meganyctiphanes norvegica (M. Sars), Thysanoessa inermis (Krøyer) and T. raschii (M. Sars) have been examined at 0°C by following the release of peptides and free amino acids.
• 2.2. The krill contains high levels of peptide hydrolases, and autoproteolysis seems to be due mainly to digestive enzymes localized in the hepatopancreas and the intestinal tract of the animals.
• 3.3. During autoproteolysis the individual amino acids were generally released at rates corresponding to their proportion in the bulk protein of the krill. The major exceptions were alanine which accumulated in amounts larger than was to be expected from the composition of the krill protein, and glutamic acid/glutamine, aspartic acid/asparagine, arginine, and to some extent glycine, proline and serine, which accumulated to a lesser extent than was to be expected.
• 4.4. Storage of krill for 1 week resulted in only minor changes in the total content of amino acids as determined after acid hydrolysis, with the exception of alanine which increased in concentration.
• 5.5. The results suggest that the formation of free alanine is partly due to reactions other than proteolysis.
• 6.6. The release of free amino acids was accompanied by a considerable increase in the amount of small peptides, and glutamic acid/glutamine, aspartic acid/asparagine, glycine and proline tended to accumulate in these peptides.
• 7.7. The autoproteolytic activity of the Thysanoessa species showed seasonal variations, probably in response to food availability. In the case M. norvegica, the results suggest that there are smaller fluctuations in the level of proteolytic enzymes, probably indicating less pronounced variations in the food intake over the year.

     

Influence of monoamine depleting pharmacologic agents on levels of activity in Caiman sclerops

• 1.1.Caimans treated with a single dose of PCPA show significantly increased activity and some behavioral modification over the first 3 days and significant decreases in activity over the next 4 days, returning to control rates by day 7.
• 2.2.Caimans pretreated with DMI and then given a single dose of 6-OHDA showed significant reduction in activity and behavioral modification over the entire 14-day study period and beyond.
• 3.3.Caimans treated with a single dose reserpine showed gradual reduction in activity over the first three post-treatment days and little change thereafter. No behavior modification was noted.
• 4.4.Caimans given a single dose of amphetamine showed a little reduction in activity but no noticeable behavioral changes over a 2-week period.
• 5.5.Caimans given a single dose of melatonin showed no significant reduction in activity but some behavioral changes, possibly attributable to reduced sensory activity.
• 6.6.An attempt is made to reconcile these findings with known changes in monoamine content of the brain.

     

Correlation between motor and electroretinographic circadian rhythms in the crayfish Procambarus bouvieri (ortmann)

• 1.1. The characteristics of both, motor and electroretinographic circadian rhythms in the crayfish Procambarus bouvieri, were examined.
• 2.2. The correlation between both rhythms in intact and brainless crayfish, was obtained.
• 3.3. The presence of at least two different but coupled oscillators responsible for the circadian variations in crayfish, is proposed.

     

Arginase,ornithine decarboxylase and S-adenosylmethionine decarboxylase in chicken brain and retina

• 1.1. Arginase, ornithine decarboxylase and S-adenosylmethionine decarboxylase are active in both retina and brain. Activity is higher in cerebellum than in the cerebral hemispheres and optical lobes.
• 2.2. Arginase and ornithine decarboxylase are very active in the retina of very young chicks, while S-adenosylmethionine decarboxylase is poorly active. By contrast, S-adenosylmethionine decarboxylase is much more active in brain.
• 3.3. The pattern of activity during development is different; only ornithine decarboxylase is very active during embryonal life; S-adenosylmethionine decarboxylase, at all events in brain, is more active in adult life.
• 4.4. Ornithine decarboxylase is inhibited in vitro by α-difluoromethylornithine, but not in vivo. Diaminopropane inhibits brain ornithine decarboxylase, but does not induce an ornithine decarboxylase-antizyme.
• 5.5. Methylglyoxal bis(guanylhydrazone) promotes an increase of S-adenosylmethionine decarboxylase activity in both the brain and the retina in vivo.