title: Effects of starvation on haemolymphatic glucose levels, glycogen contents and nucleotidase activities in different tissues of Helix aspersa (Müller, 1774) (Mollusca, Gastropoda).
abstract: 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.
authors.affiliation: Laboratório de Pesquisa Bioquímica, Departamento de Ciências Fisiológicas, Faculdade de Biociências, Pontifícia Universidade Católica do Rio Grande do Sul, Caixa postal 1429, 90619-900, Porto Alegre, RS, Brazil.
authors.forename: Eliane
authors.initials: E
authors.lastname: Borges
authors.forename: Fernanda Cenci
authors.initials: FC
authors.lastname: Vuaden
authors.forename: Giana de Paula
authors.initials: Gde P
authors.lastname: Cognato
authors.forename: Maria da Graça
authors.initials: Mda G
authors.lastname: Fauth
authors.forename: Carla Denise
authors.initials: CD
authors.lastname: Bonan
authors.forename: Guendalina
authors.initials: G
authors.lastname: Turcato
authors.forename: Isabel Cristina da Costa
authors.initials: IC
authors.lastname: Rossi
authors.forename: Renato Dutra
authors.initials: RD
authors.lastname: Dias
mesh_terms: D000251:Adenosine Triphosphatases / Q000378:metabolism; D000704:Analysis of Variance; D000818:Animals; D001786:Blood Glucose; D001938:Brazil; D002118:Calcium / Q000378:metabolism; D004064:Digestive System / Q000378:metabolism; D017952:Ganglia, Invertebrate / Q000378:metabolism; D006003:Glycogen / Q000378:metabolism; D006372:Helix, Snails / Q000502:physiology*; D006458:Hemolymph / Q000737:chemistry*; D009708:Nucleotidases / Q000378:metabolism; D013217:Starvation / Q000097:blood*
chemical_list: D001786:Blood Glucose; D006003:Glycogen; D009708:Nucleotidases; C030287:nucleotidase; D000251:Adenosine Triphosphatases; D002118:Calcium