The half-life and uptake of 14c-1-ascorbic acid in selected organs of rainbow trout (salmo gairdneri)

• 1.1. The uptake and apparent half-life of ¹⁴C-1-ascorbic acid was determined in selected organs of rainbow trout over an 84 day period.
• 2.2. Brain ascorbic acid concentrations in the trout were consistently higher than those in the other tissues measured.
• 3.3. Uptake of ¹⁴C radioactivity by whole brain tissues of the trout was initially lower than in the other tissues; however, ¹⁴C radioactivity continued to increase in this organ until 42 days post-injection. This would indicate that whole brain tissues of the trout take a long time to reach an equilibrium state and suggests the existence of a blood-brain barrier to ascorbic acid in the central nervous system of the trout.
• 4.4. The half-life of ascorbic acid in selected organs of the rainbow trout appears to be very much longer than that of other animals.
• 5.5. Specific activity measurements suggest that the rainbow trout has a slow rate of synthesis of ascorbic acid.

     

Immobilization stress-induced antioxidant defense changes in rat plasma: Effect of treatment with reduced glutathione

• 1.1. We examined immobilization stress-induced antioxidant defense changes in rat plasma and observed the antioxidant effect of reduced glutathione (GSH) administration on these changes.
• 2.2. Immobilization stress induced severe bleeding in the stomach and a significant increase in plasma levels of thiobarbituric acid receives substances (TBARS).
• 3.3. Immobilization stress induced a significant decrease in plasma iron-binding, ironoxidizing protections and radical scavenging activity.
• 4.4. Plasma levels of ascorbic acid, ascorbyl radical and superoxide dismutase activity remained unchanged following immobilization stress.
• 5.5. Treatment with GSH showed a significant protective effect on stomach bleeding, on the increase in plasma TEARS, and on the decrease of iron-binding, iron-oxidizing protection and radical scavenging activity in plasma.
• 6.6. These results suggest that immobilization stress induces generation of reactive oxygen species and decreases the endogenous antioxidant defenses, which can be attenuated by extracellular administration of antioxidant GSH.

     

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.

     

Further studies on the mechanism of action of gossypol on mitochondrial membrane

• 1.1. In order to explore the mechanism of inhibition of hydroxylases involved in steroidogenesis, by gossypol, we studied the effect of this drug on adrenal cortex mitochondria, and compared it with those on kidney and heart.
• 2.2. The uncoupler effect of gossypol (collapse of Δψ and Ca²⁺ efflux) was found to be lower in adrenal cortex mitochondria than in kidney and heart mitochondria.
• 3.3. Gossypol produced more extensive changes on the membrane lipidic matrix (increase in the order parameter for 5-doxylstearic acid) in adrenal cortex mitochondria than in the other mitochondria studied.
• 4.4. The results described above indicate that the mechanism of inhibition of gossypol of steroidogenic adrenal enzymes could be attributed to an alteration of the lipidic matrix which, in turn, modifies protein function.

     

Glucosyl and galactosyl transferase activities of diabetic (db/db) and obese (ob/ob) mice kidneys

• 1.1. Glucosyl and galactosyl activities were determined in kidney cortex tissue prepared from two strains of mice, genetically diabetic and obese mice.
• 2.2. These activities were measured as a function of ageing between 6 weeks and 13 months.
• 3.3. For both strains glucosyl transferase activity was shown to increase with respect to ageing whereas galactosyl transferase activity decreased at the same time.
• 4.4. These changes of enzymatic activities would suggest that a smaller increase of hydroxylysine-linked glycans than expected was observed under these pathological conditions.

     

Sympathoadrenal activity during helox-cold induced hypothermia in syrian hamsters

• 1.1. As reflected by increasing plasma concentrations of cortisol, norepinephrine, epinephrine and dopamine, a marked stimulation of the adrenal cortex and of the sympathetic nervous system occurred in Syrian hamsters during moderate hypothermia induced by helium-oxygen atmosphere and cold.
• 2.2. A profound hyperglycemia was observed during hypothermia.
• 3.3. All effects due to the helium-oxygen atmosphere and cold exposure (helox-cold) disappeared almost completely after rewarming.
• 4.4. The results corroborate the hypothesis of an involvement of the adrenal cortex combined with the sympathetic nervous system in the control of acute induced heat production.

     

Blood lipids of the small octopus,Octopus tehuelchus (mollusca,cephalopoda) at different stages of sexual maturation

• 1.1. The lipid and fatty acid composition from the plasma and hemocytes in Octopus tehuelchus at different stages of sexual development, was determined.
• 2.2. The highest content of lipids was found in females engaged in egg development, and the lowest in post-spawning and brooding females. Highest levels occurred during the autumn season in both sexes.
• 3.3. Changes were mainly due to triacylglycerols and diacylglyceryl ethers.
• 4.4. The plasma fatty acid composition did not demonstrate significant changes at different stages of maturation. The arachidonic acid (20:4 ω 6) was present at surprisingly high levels.

     

Role of arginase transferred from the vesicula seminalis during mating and changes in amino acid pools of the spermatophore after ejaculation in the silkworm,Bombyx mori

.

• 1.1. Ejaculation of seminal fluid into the spermatophore formed inside the female bursa copulatrix terminates 20 min after the beginning of copulation of Bombyx mori. The amounts of amino acids transferred are small, but the amounts of amino acids in the spermatophore continue to increase after this time due to protein degradation and amino acid interconversions.
• 2.2. Arginase, which has high activity in the vesicula seminalis, is transferred to the spermatophore without loss of activity during ejaculation. During mating, ornithine and much urea are formed in the spermatophore, indicating activity of the transferred arginase.
• 3.3. In the spermatophore, marked increase of alanine with low concentrations of ornithine and glutamate suggests the presence of a pathway for the active formation of 2-oxoglutarate with pyruvate via glutamate from arginine. During mating, proline and glutamine also increase, but at low rates.
• 4.4. Of the exocrine glands in the male reproductive system, the vesicula seminalis secretes the highest concentration of glutamate (30% of the total amino acids); serine is the amino acid present at highest concentration in secretions of other glands (20–30%). No urea was found in the secretions of any of the glands.

     

Purification and characterization of haemagglutinin in the haemolymph of the silkworm,Bombyx mori

• 1.1. Changes in haemagglutinating activity in haemolymph during 4th and 5th larval instars of Bombyx mori were stage specific. The activity increased in time concomitant with an increase in the secretory activity of prothoracic glands.
• 2.2. The protein with haemagglutinating activity was purified by ammonium sulfate fractionation, gel-filtration on Sephacryl S-300 and affinity chromatography using either glucuronic acid or galacturonic acid as a ligand.
• 3.3. Western blotting analysis using antibody raised against this protein revealed that Bombyx haemagglutinin is a tetramer composed of two different subunits with mol. wts of ca 88,000 and 90,000.

     

Seasonal changes of circulating blood parameters in the grass snake Natrix natrix natrix L.

• 1.1. Seasonal changes of circulating blood parameters of Natrix n. natrix were evident and involved both sexes to the same extent.
• 2.2. A significant decrease in red cell count, haematocrit and haemaglobin concentration in the mating period, and an increase in those parameters and mean cell volume in autumn were observed, and haemodilution during winter torpor.
• 3.3. The changes during the breeding season had probably a hormonal background; in winter, they resulted first of all from a decreased erythropoietic activity and, to a lesser extent, from an increased red blood cell breakdown rate. However, the possibility that some erythrocytes were withdrawn from the circulation cannot be excluded.
• 4.4. Winter lymphocytopenia, eosinocytopenia and neutrophilic granulocytosis in females during egg laying were expressions of changes of leucocyte formula.
• 5.5. Seasonal cyclicity was found only with respect to the white cell count in males and the eosinophile fraction in males and females.
• 6.6. Probable reasons for, and mechanisms of the changes in blood composition are discussed.

     

Kinetic studies of catechol-o-methyltransferase from the brain of the African catfish,Clarias gariepinus

• 1.1. Optimum in vitro conditions, and kinetics of the enzyme catechol-O-methyltransferase from the brain of the male African catfish were studied.
• 2.2. A saturated level for S-adenosylmethionine, as methyldonor, and magnesium as cofactor was reached at 5 μM and 10 mM, respectively.
• 3.3. The addition of ascorbic acid, as an antioxidant, and tranylcypromine, as a MAO inhibitor, was not necessary, during incubations with fore-brain homogenates.
• 4.4. Kinetic analysis of the methylation of catecholestrone, catecholestradiol and dopamine showed K_m values of 1.2, 0.6 and 0.5 μM, respectively.
• 5.5. The affinity of the catecholsubstrates for the enzyme catechol-O-methyltransferase is much higher in the brain of the African catfish than in tissues of mammals.

     

Induction of a 60-kDa heat shock protein in rat pancreas by water-immersion stress

• 1.1. In this study, expression of a 60-kDa heat shock protein in rat pancreas was investigated before and after water-immersion stress, which has been known as an exacerbation factor of caerulein-induced pancreatitis in rats, by Western blot.
• 2.2. A 60-kDa heat shock protein increased after water-immersion stress in both soluble and insoluble fractions of the pancreas.
• 3.3. Serum amylase level and pancreas weight did not increase after water-immersion.
• 4.4. No pathologic alteration was observed in the pancreas after water-immersion.

     

The effect of cortisol on stimulation of enzymatic activity and absorption of amino acids in the small intestine of adult hamsters

• 1.1. The s.c. administration of cortisol to hamsters (50 mg/kg body wt/day for 4 days) produces a significant increase in maltase sucrase, alkaline phosphatase and leucineaminopeptidase activity in intestinal mucosa.
• 2.2. Lactase activity is unaffected by cortisol.
• 3.3. Gamma-glutamyltranspeptidase activity increases slightly in females but remains unchanged in males.
• 4.4. Cortisol causes increase in proline and glycine absorption without changing the absorption of lysine.

     

Sex differences in vascular reactivity to adrenergic agents in the rat

• 1.1.The study was designed to determine if there are sex-dependent differences in vascular reactivity to adrenergic agents.
• 2.2.Vascular reactivity of both aortic and tail artery smooth muscle from male and female rats to various vasoactive agents was assessed. 3.li]The vascular response of aortic smooth muscle to both phenylephrine and isoproterenol were significantly greater in male rats as compared to females.
• 3.4.There were apparent sex differences in responsiveness to the KCl-induced, non-receptor mediated contraction of aortic smooth muscle in that the sensitivity to KCl was enhanced in male rats.
• 4.5.No sex differences were observed in tail artery preparations.
• 5.6.Phentolamine reduced the maximal tension induced by KCl in the tail artery but not aortic artery preparations. This effect was not sex dependent.
• 6.7.No differences in the vascular smooth muscle responsiveness to acetylcholine or sodium nitrate was observed between groups or within different vascular beds.
• 7.8.The increased sensitivity of males to adrenergic challenge could explain in part some of the existing sex differences in cardiovascular disease and hypertension.

     

Main serum protein of rainbow trout (Salmo gairdnerii): its biological properties and significance

• 1.1. Main serum α₁-protein (α₁P) of rainbow trout was purified and its biochemical and physico-pathological properties were studied.
• 2.2. α₁P was suggested to be a primitive protein having both properties of albumin and AFP in serum proteins of mammals according to the following results.
• 3.3. Molecular weight (75,000), two kinds of molecules (pI 4.55 and 5.05) and amino acid composition.
• 4.4. Dye- or ConA binding activity.
• 5.5. Estrogen binding activity and inhibitory effect on lymphoblastoid-forming activity.
• 6.6. Possible osmotic regulator.
• 7.7. Significant elevation of blood α₁P level in the course of hepatoma induction.

     

Variations in the levels of progesterone in Mytilus edulis during the annual reproductive cycle

• 1.1. Progesterone levels in Mytilus edulis males and females during the annual reproductive cycle were analysed in the whole animal and in the gonads using gas-liquid chromatography and radioimmunoassays.
• 2.2. The high hormone levels in the whole animal were observed in July and October, coincident with the main spawning seasons.
• 3.3. The levels of progesterone in gonad extracts also show a maximum in summer (July).
• 4.4. The patterns of the progesterone levels in males and females throughout the annual reproductive cycle are similar.
• 5.5. These data are discussed in relation to the role of progesterone in the regulation of sex-specific processes, particularly gametogenesis.

     

Properties of ferredoxin reductase and ferredoxin from the bovine corpus luteum

• 1.1. Ferredoxin reductase and ferredoxin were purified from the bovine corpus luteum and their properties compared to the corresponding adrenal proteins.
• 2.2. The luteal and adrenal proteins had similar absorbance spectra and molecular weights.
• 3.3. Evidence was obtained from spectrophotometric titrations for formation of 1:1 complexes between luteal ferredoxin reductase and ferredoxin and between ferredoxin and cytochrome P-450_scc.
• 4.4. Adrenal ferredoxin reductase and ferredoxin were equally as effective as luteal ferredoxin reductase and ferredoxin in supporting cholesterol side-chain cleavage by luteal cytochrome P-450_scc.

     

Gender-related differences of mouse liver d-aspartate oxidase in the activity and response to administration of d-aspartate and peroxisome proliferators

• 1.1. The hepatic d-aspartate oxidase activity was found to be higher in female ddY and ICR mice than in their male counterparts. On the contrary, the free d-aspartate content in the liver was lower in female mice than in male mice, suggesting that d-aspartate is actually metabolized by d-aspartate oxidase in vivo.
• 2.2. Oral administration of d-aspartate to the animals increased the hepatic d-aspartate oxidase activity 2–3 fold in both genders without any significant difference in the rate of the increase between the genders.
• 3.3. Several peroxisomal enzyme activities other than d-aspartate oxidase examined were not affected by this treatment.
• 4.4. Experiments in vitro suggested that the increase in the d-aspartate activity might be explained in part by stabilization of the enzyme by d-aspartate.
• 5.5. The administration of clofibrate, a peroxisome proliferator, to male mice, increased the hepatic d-aspartate oxidase activity with a significant simultaneous decrease of d-aspartate content in the liver, in agreement with a possible role of the enzyme n vivo.
• 6.6. On the other hand, the administration of clofibrate or dehydroepiandrosterone to female mice decreased the d-aspartate oxidase activity.
• 7.7. The peroxisome proliferators were suggested to act to eliminate the gender difference of hepatic d-aspartate oxidase activity in mice.

     

Acylation of lysoglycerophospholipids by adrenal membranes

• 1.1. Substantial differences were found in the acyi donor and lyso-acceptor specificities among subcellular membranes and with respect to different regions of the adrenal gland.
• 2.2. In the presence of Mg²⁺-ATP and CoASH, adrenal microsomes were actively transferring arachidonate to lysophospholipids with acyl acceptor specificity in the order: 1-acyl-GPI > 1-acyl-GPC > 1-acyl-GP. However, when oleoyl-CoA was used, acyi acceptor specificity for the microsomal transferases was in the order: 1-acyl-GPC > 1-acyl-GP > 1-acyl-GPI.
• 3.3. Mitochondrial membranes had very low acyi transfer activity and they preferred 1-acyl-GPC over other lyso-acceptors.
• 4.4. The chromamn granules were apparently lacking this type of activity.

     

Some hematological data from marsh harriers (Circus aeruginosus) in central spain

• 1.1. Hematocrit, total protein and glucose values were determined in blood samples from 19 marsh harriers (Circus aeruginosus), 10 males and nine females.
• 2.2. The different parameters were studied on the basis of the ranges described in other birds.
• 3.3. There was a significant correlation between weight and blood glucose level.