Embriogenesis Ikan Betok (Anabas Testudineus) Pada Suhu Inkubasi Yang Berbeda
Prolonged air-breathing and recovery modify the thyroid and interrenal axes in climbing perch...
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Total CO 2 of plasma and intestinal fluids transiently increased and then significantly decreased, demonstrating the consecutive overloading and adjustment of branchial H + extrusion. Total rectal base excretion increased from normal (59.75 ± 18.2 μmol/kg/h) to elevated (182.67 ± 64.1 μmol/kg/h) salinity, as did branchial acid secretion (229.70 ± 38.5 to 403.06 ± 32.9 μmol/kg/h). These results support the hypothesis of branchial compensation for the systemic acidosis caused by increased intestinal HCO 3 − secretion, asso- ciated with the osmoregulatory demands of elevated salinity. doi:10.1016/j.cbpa.2007.01.142 A3.25 Growth hormone and Prolactin-1 gene transcription in natural populations of the black-chinned tilapia Sarotherodon melanotheron acclimatised to different salinities M. Tine, (IRD/UMII Montpellier, France); J. de Lorgeril, (IFREMER Montpellier, France); J. Panfili, J. Durand, (IRD Montpellier, France), K. Diop, (IRD Dakar, Senegal); F. Bonhomme, (CNRS Montpellier, France) The effects of salinity on the expression of genes coding for growth hormone (GH) and prolactin-1 (PRL1) were studied in various natural populations of the black-chinned tilapia Sar- otherodon melanotheron coming from West Africa. Individuals were sampled in June 2005 in six locations in Senegal and the Gambia, at salinities of between 0 and 101. The poorest condition factors were recorded in the most saline sampling site and the best growth in the fish marine environment. The pituitary GH mRNA levels were significantly higher in fish adapted to seawater, whereas the PRL1 mRNA levels were highest in fish adapted to fresh- and brackish water. These results show that the PRL1 mRNA levels reflected relatively well the differences in environmental salinity, in contrast to those of GH, which tended instead to reflect the individual growth in relation to their environment. However, no relation could be found between the growth in the hypersaline areas and the expression profile of the GH. Although the fish analysed were morphologically identical, the expression of genes coding for GH and PRL1 showed large differences between indivi- duals. This inter-individual variation in gene expression remains poorly understood. doi:10.1016/j.cbpa.2007.01.143 A3.26 Prolonged air-breathing and recovery modify the thyroid and interrenal axes in climbing perch (Anabas testudineus) S. Peter, (University of Kerala, India); S. Wendelaar Bonga, (Radboud University of Nijmegen, The Netherlands) To examine the response of thyroid and intrenal axes to hydromineral and metabolic responses in air-breathing fish during their territorial migration, we quantified several physiological markers in the tropical obligate air-breathing perch (Anabas testudineus) during air breathing on land and in water. Plasma T 3 and T 4 levels remained unaffected after 60 and 120 min of air breathing though T 3 had a tendency to increase. Plasma cortisol levels showed a significant 4-fold increase. Plasma cortisol showed a 1.5-fold increase in these recovered fish. Air breathing on land significantly increased plasma glucose (2.8-fold) and plasma urea (5.2-fold) while plasma lactate showed a significant 3.2-fold decrease. Na + ,K + -ATPase activity, reflecting the sodium pump activity, showed a 4.4-fold decrease in the gills but produced a 1.8-fold increase in the kidneys after air exposure for 120 min. Significant reversal of the plasma metabolite values and the gill Na + ,K + -ATPase activity (15-fold) was obtained during recovery. The immunor- eactivity of Na + ,K + -ATPase in the branchial chloride cells (CCs) showed little changes. The density of the CCs remained unaffected. A marked increase of the glucocorticoid receptor staining was observed in air-exposed gills. Analyses of the ultrastructure of the branchial epithelia revealed CCs with low Na + ,K + -ATPase immunoreactivity, more macro- phages and increased intercellular spaces in the air-exposed fish. Our data for the first time provide evidence that the thyroid and interrenals jointly direct adaptive strategies to recover from the stress during prolonged air-breathing thus supporting the hypothesis of a role for thyroid in stress adaptation in fish. doi:10.1016/j.cbpa.2007.01.144 A3.27 Earthworm osmoregulation: Aquaporins in a non-model invertebrate E. Campbell, S. Hoppler, A. Bowman, (University of Aberdeen, United Kingdom) The discovery and subsequent characterisation of aquaporins (AQPs) represents an important step towards the understanding of osmoregulation. Much research to date has focused on AQPs in plant, bacterial, insect and higher animal systems, with other invertebrate groups less well studied. Earthworms are of huge ecological importance; indeed they are the largest contributors to soil invertebrate biomass, recycling nutrients, aerating, mixing and improving the drainage of soils. They are also of evolutionary significance representing a phylum that has bridged the gap between marine and terrestrial modes of life. The present study examines AQPs in the terrestrial oligochaete Lumbricus rubellus. The full length sequences of two aquaporins, LrAQPA and LrAQPG, have been obtained and analysed. LrAQPA contains two NPA motifs that are highly conserved throughout the AQP family. LrAQPG is unusual in S95 Abstracts / Comparative Biochemistry and Physiology, Part A 146 (2007) S87–S96
Transcript of Prolonged air-breathing and recovery modify the thyroid and interrenal axes in climbing perch...
S95Abstracts / Comparative Biochemistry and Physiology, Part A 146 (2007) S87–S96
Total CO2 of plasma and intestinal fluids transientlyincreased and then significantly decreased, demonstratingthe consecutive overloading and adjustment of branchialH+ extrusion. Total rectal base excretion increased fromnormal (59.75±18.2 μmol/kg/h) to elevated (182.67±64.1 μmol/kg/h) salinity, as did branchial acid secretion(229.70±38.5 to 403.06±32.9 μmol/kg/h). These results supportthe hypothesis of branchial compensation for the systemicacidosis caused by increased intestinal HCO3
− secretion, asso-ciated with the osmoregulatory demands of elevated salinity.
doi:10.1016/j.cbpa.2007.01.142
A3.25Growth hormone and Prolactin-1 gene transcription innatural populations of the black-chinned tilapiaSarotherodonmelanotheron acclimatised to different salinities
M. Tine, (IRD/UMII Montpellier, France); J. de Lorgeril,(IFREMER Montpellier, France); J. Panfili, J. Durand, (IRDMontpellier, France), K. Diop, (IRD Dakar, Senegal); F.Bonhomme, (CNRS Montpellier, France)
The effects of salinity on the expression of genes coding forgrowth hormone (GH) and prolactin-1 (PRL1) were studied invarious natural populations of the black-chinned tilapia Sar-otherodon melanotheron coming from West Africa. Individualswere sampled in June 2005 in six locations in Senegal and theGambia, at salinities of between 0 and 101. The poorestcondition factors were recorded in the most saline sampling siteand the best growth in the fish marine environment. Thepituitary GH mRNA levels were significantly higher in fishadapted to seawater, whereas the PRL1 mRNA levels werehighest in fish adapted to fresh- and brackish water. Theseresults show that the PRL1 mRNA levels reflected relativelywell the differences in environmental salinity, in contrast tothose of GH, which tended instead to reflect the individualgrowth in relation to their environment. However, no relationcould be found between the growth in the hypersaline areas andthe expression profile of the GH. Although the fish analysedwere morphologically identical, the expression of genes codingfor GH and PRL1 showed large differences between indivi-duals. This inter-individual variation in gene expressionremains poorly understood.
doi:10.1016/j.cbpa.2007.01.143
A3.26Prolonged air-breathing and recovery modify the thyroidand interrenal axes in climbing perch (Anabas testudineus)
S. Peter, (University of Kerala, India); S. Wendelaar Bonga,(Radboud University of Nijmegen, The Netherlands)
To examine the response of thyroid and intrenal axes tohydromineral and metabolic responses in air-breathing fishduring their territorial migration, we quantified severalphysiological markers in the tropical obligate air-breathingperch (Anabas testudineus) during air breathing on land and inwater. Plasma T3 and T4 levels remained unaffected after 60 and120 min of air breathing though T3 had a tendency to increase.Plasma cortisol levels showed a significant 4-fold increase.Plasma cortisol showed a 1.5-fold increase in these recoveredfish. Air breathing on land significantly increased plasmaglucose (2.8-fold) and plasma urea (5.2-fold) while plasmalactate showed a significant 3.2-fold decrease. Na+,K+-ATPaseactivity, reflecting the sodium pump activity, showed a 4.4-folddecrease in the gills but produced a 1.8-fold increase in thekidneys after air exposure for 120 min. Significant reversal ofthe plasma metabolite values and the gill Na+,K+-ATPaseactivity (15-fold) was obtained during recovery. The immunor-eactivity of Na+,K+-ATPase in the branchial chloride cells(CCs) showed little changes. The density of the CCsremained unaffected. A marked increase of the glucocorticoidreceptor staining was observed in air-exposed gills. Analysesof the ultrastructure of the branchial epithelia revealed CCswith low Na+, K+-ATPase immunoreactivity, more macro-phages and increased intercellular spaces in the air-exposedfish. Our data for the first time provide evidence that thethyroid and interrenals jointly direct adaptive strategies torecover from the stress during prolonged air-breathing thussupporting the hypothesis of a role for thyroid in stressadaptation in fish.
doi:10.1016/j.cbpa.2007.01.144
A3.27Earthworm osmoregulation: Aquaporins in a non-modelinvertebrate
E. Campbell, S. Hoppler, A. Bowman, (University ofAberdeen, United Kingdom)
The discovery and subsequent characterisation of aquaporins(AQPs) represents an important step towards the understandingof osmoregulation. Much research to date has focused on AQPsin plant, bacterial, insect and higher animal systems, with otherinvertebrate groups less well studied. Earthworms are of hugeecological importance; indeed they are the largest contributorsto soil invertebrate biomass, recycling nutrients, aerating,mixing and improving the drainage of soils. They are also ofevolutionary significance representing a phylum that hasbridged the gap between marine and terrestrial modes of life.The present study examines AQPs in the terrestrial oligochaeteLumbricus rubellus. The full length sequences of twoaquaporins, LrAQPA and LrAQPG, have been obtained andanalysed. LrAQPA contains two NPA motifs that are highlyconserved throughout the AQP family. LrAQPG is unusual in
