Effects of starvation on haemolymphatic glucose levels, glycogen contents and nucleotidase activities in different tissues of Helix aspersa (Müller, 1774) (mollusca, gastropoda) (original) (raw)
Related papers
Journal of Experimental Zoology, 2004
In the present study, the glucose concentration in the haemolymph and glycogen levels were determined in the various body parts of the Helix aspersa snail after feeding lettuce ad libitum and after various periods of starvation. To characterize the effect of starvation on nucleotidase activity, enzyme assays were performed on membranes of the nervous ganglia and digestive gland. Results demonstrated the maintenance of the haemolymph glucose concentration for up to 30 days of starvation, probably due to the consumption of glycogen from the mantle. In the nervous ganglia, depletion of glycogen occurs progressively during the different periods of starvation. No significant changes were observed on ATP and ADP hydrolysis in the membranes of nervous ganglia and no alterations in Ca2+- ATPase and Mg2+-ATPase occurred in the membranes of the digestive gland of H. aspersa during the different periods of starvation. Although there were no changes in the enzyme activities during starvation, they could be modulated by effectors in situ with concomitant changes in products/reactants during starvation. J. Exp. Zool. 301A:891–897, 2004. © 2004 Wiley-Liss, Inc.
2009
The present study was designed to investigate histochemically the detection of carbohydrate and protein in the normally feeding snails and after 15 and 30 days of starvation. Generally, abundant carbohydrate and protein materials were detected in the component cells of the digestive gland of normally feeding snails. The results of this investigation revealed a pronounced decline of carbohydrates in the digestive gland cells of Monacha cartusiana snails after starvation. Severe decline in carbohydrate content was observed especially after 30 days of starvation. Moreover, protein inclusions have exhibited a week stainability in the digestive gland cells of these snails as a consequence of starvation.
Comparative Biochemistry and Physiology Part B: Biochemistry and Molecular Biology, 2004
Nucleotide-metabolizing enzymes play an important role in the regulation of nucleotide levels. In the present report, we demonstrated an enzyme activity with different kinetic properties in membrane preparations of the nervous ganglia and digestive gland from Helix aspersa. ATPase and ADPase activities were dependent on Ca and Mg with pH 2q 2q optima approximately 7.2 and between 6.0 and 8.0 in digestive gland and nervous ganglia, respectively. The enzyme activities present in membrane preparations of these tissues preferentially hydrolyzed triphosphate nucleotides. In nervous ganglia, the enzyme was insensitive to the classical ATPases inhibitors. In contrast, in digestive gland, N-ethylmaleimide (NEM) produced 45% inhibition of Ca-ATP hydrolysis. Sodium azide, at 100 mM and 20 mM, inhibited Mg-ATP 2q 2q hydrolysis by 36% and 55% in digestive gland, respectively. The presence of nucleotide-metabolizing enzymes in these tissues may be important for the modulation of nucleotide and nucleoside levels, controlling their actions on specific purinoceptors in these species.
Generally, the aestivating snails maintain an anaerobic mode of life with low metabolic activities. To verify this statement, activities of thirteen metabolic enzymes have been studied in digestive gland, ovotestis and mantle of Achatina fulica, a hermaphrodite pulmonate snail. Enzymes were assayed from these organs in both control and aestivating (15, 30, 45, 60 and 90 days) snails. The results indicate that the above three organs exhibit different levels of activities with regard to most of the metabolic enzymes that have been studied. The results reveal that most of the enzymes show higher activities in ovotestis during aestivation followed by digestive gland, while mantle does not show any remarkable change. It is further concluded that during aestivation A. fulica maintains, at least partially, aerobic state of life.
2004
Juveniles of the white shrimp Litopenaeus vannamei were kept Without food for between 0 to 15 clays to evaluate the impact of starvation oil physiologic state (oxygen consumption, poststarvation refeeding, index, nitrogen excretion, and O:N ratio) and digestive enzymes activity. Physiologic changes were found after 6 days of fasting, and refeeding ability declined as a result. Nevertheless. the shrimp were able to Survive 16 days Without food. Starvation Caused metabolism to drop progressively toward a basal level (21 J (.) h(-1 .) g(-1)) and a decrease in the rate of ammonia excretion, because of the catabolism of amino acids front soluble protein in the hepatopancreas. This decrease led to an increase in digestive enzymes specific activity (U/mg protein). But, expressed as total U. all digestive enzyme activities decreased in the absence of substrate from 0.016 to 0.007 U/hepatopancreas (HP) for alpha-amylase and 2.58 to 0.63 U/HP for total trypsin. L. vannamei juveniles showed a true physiologic adaptation mechanism to food depiivation: no changes in body weight but loss in hepatosomatic index, no exuviations, including the utilization of HP soluble proteins (a drop from 269 to 53 mg/mL). After 10 days. a neoglycogenic pathway and the corresponding tissue enzymes activities seemed enhanced, and the animals derived all energetic Substrates mainly from protein (O:N ratio of 17) to cover their metabolic costs. Estimates of basal metabolism (Hem) from the routine respiration rate per clay (from 361 to 725 J (.) g ww(-1) (.) day(-1) through the 15-day starvation period). and loss of nonfecal energy (HxE) from the nitrogen excretion rate (varying from 39 to 57 J (.) g ww(-1) (.) day(-1) during the same period) were used in a bioenergetic partition model of a fasting juvenile. Which indicated that the energetic requirement to Survive Without feeding was in the range of 418 and 771 J (.) g ww(-1) (.) day(-1) during the 15-day period of starvation.
Protoplasma, 1979
The ultrastructural localizations of thiolacetic acid esterase, indoxyl acetate esterase and acid (5-glycerophosphatase have been studied in the digestive gland cells of fed and starved Cepaea nemoralis. In fed snails the major localization of all three enzymes was in the green granule vacuoles of digestive cells. In addition, the cytoplasm of calcium cells and the Golgi apparatus and GERL (?) of all cell types were acid phosphatase positive. Many digestive cells of starved snails showed a similar enzyme distribution to that found in fed snails but other digestive cells showed a very high cytoplasmic activity of all three enzymes. It is suggested that these cells are in the process of autolysis. New light is also thrown on the process by which food is transported from the digestive gland lumen to the phagosomes of digestive cells.
Comparative Biochemistry and Physiology Part B: Comparative Biochemistry, 1990
The foot muscle of P. caerulea has a complete sequence of glycolytic enzymes. The low activity of hexokinase, in comparison with the activities of glycogen phosphorylase and phosphofructokinase, indicate that glycogen is the main fuel oxidized. 2. The reduction of aspartate content in combination with the accumulation of alanine and the presence of considerable activities of glutamate-oxaloacetate transaminase and glutamate~pyruvate transaminase indicates a coupled metabolism of glycogen and aspartate during exposure to air. 3. From the changes in the concentration of the metabolites during exposure to air it appears that up to the second hour of anaerobiosis alanine, lactate and glutamate are the end-products which accumulate in the foot muscle of P. caerulea, whereas from the second to the fourth hour only succinate and alanine accumulate. 4. The low activities of the Krebs cycle enzymes as well as the absence of ~t-ketoglutarate dehydrogenase activity suggest that the Krebs cycle is not in operation. 5. The absence of opine dehydrogenases shows that the end products octopine, alanopine and strombine are not accumulated in the foot muscle under anaerobiosis. 6. The high activity of malate dehydrogenase in the direction of malate formation in combination with the low activity of ~-lactate dehydrogenase and the absence of opine dehydrogenases suggests that the former dehydrogenase is coupled 1 : 1 to glyceraldehyde-3-phosphate dehydrogenase.
Comparative Biochemistry and Physiology C-toxicology & Pharmacology, 2007
In a previous study we analysed the effect of diesel seawater contamination in the digestive gland of the Antarctic limpet Nacella concinna. We observed that antioxidant enzyme activities decreased after one-week starvation prior to the experiment, and this was considered in the analysis of the obtained results. To know whether the digestive gland oxidant-antioxidant status may be altered by starvation and experimental conditions, we evaluated the food deprivation effect in limpets from the nearshore shallow waters of Potter Cove, Antarctica. Organisms were acclimated to laboratory conditions and were divided in fed and starved groups, and maintained in these conditions during one month. Every week 20 limpets were sampled from each group. Digestive glands were dissected and kept frozen until they were processed. Superoxide dismutase (SOD), catalase (CAT) and glutathione S-transferase (GST) activities, as well as lipid peroxidation (LPO) measured as thiobarbituric reactive substances (TBARS), protein oxidation (PO) and reduced glutathione (GSH) were measured. For both groups of limpets, SOD increased its activity in the first week of the exposure period, with a maximum in the second week. CAT activity increased significantly in the second week, only for the starved group. Similarly, GST activity also increased for starved group in the second week; but maintained this tendency for both groups until the fourth week. In fed and starved limpets, TBARS values increased significantly, during the first week and then returned to normal values. The PO levels in the starved group increased only during the first week. The GSH content, for the fed group, increased significantly after the third week. The obtained results indicate that biochemical or physiological studies conducted with N. concinna should consider the effects of food deprivation and time spent under experimental conditions. Comparative Biochemistry and Physiology, Part C 146 118 -123 www.elsevier.com/locate/cbpc ☆ This paper is part of the 4th special issue of CBP dedicated to The Face of Latin American Comparative Biochemistry and Physiology organized by Marcelo Hermes-Lima (Brazil) and co-edited by Carlos Navas (Brazil), Rene Beleboni (Brazil), Rodrigo Stabeli (Brazil), Tania Zenteno-Savín (Mexico) and the editors of CBP. This issue is dedicated to the memory of two exceptional men, Peter L. Lutz, one of the pioneers of comparative and integrative physiology, and Cicero Lima, journalist, science lover and Hermes-Lima's dad. ⁎ Corresponding author. Tel./
Memórias do Instituto Oswaldo Cruz, 2001
Aminotransferases (GOT and GPT) activities in the hemolymph of Bradybaena similaris under experimental condition of starvation were studied. At the 10th day of starvation, GOT activity was 416.6% higher than that observed in the fed snails, being reduced and ranging values near to that shown by the control group onwards. GPT activity only varied significantly at the day-30 of starvation. The results were discussed.
Neurosecretory Cell Protein Metabolism in the Land Snail,Otala Lactea
Journal of Neurochemistry, 1976
Protein synthesis in an identified molluscan neurosecretory cell of the land snail, U t a h lactea was examined using three different types of polyacrylamide gel electrophoresis. Cells taken from active snails synthesized specific low molecular weight proteins while those from aestivated snails did not. Most of the newly synthesized low molecular weight proteins in the active snails were lost from the cell body when the preparations was chased for 19 h in label-free enriched medium in the presence of anisomycin, an inhibitor of protein synthesis. If colchicine, a blocker of axonal transport, was included in the chase medium, the proteins present following a pulse were largely replaced by smaller molecular weight species. The results suggest that specific low molecular weight proteins are converted to smaller species and then transported from the cell body.