... circulating glucose concentrations. In contrast to mammals, the glucose-lowering effect does not involve activation of AMPK. Amino acids Glycolysis Gluconeogenesis AMPK signaling Gene expression Enzyme activity Natural Sciences and Engineering Research Council of Canada http://dx.doi.org...

...Antonio Brun; Melisa E. Magallanes; William H. Karasov; Enrique Caviedes-Vidal ABSTRACT Although dietary flexibility in digestive enzyme activity (i.e. reaction rate) is widespread in vertebrates, mechanisms are poorly understood. When laboratory rats are switched to a higher protein diet...

... whole-animal metabolism more efficient. Here, we tested the applicability of the MPT to a marine ectotherm, the mussel Mytilus edulis at the intraspecific level. We determined effects of body mass on whole-organism, tissue and cellular oxygen consumption rates, on heart rate, metabolic enzyme activities...

...: The frequencies of reliable and unreliable signals of strength in Uca vomeris are influenced by the structural and physiological mechanisms behind force production in the major claw. Signal reliability Claw regeneration Enzyme activity Muscle physiology Claw biomechanics Performance...

... habitats (∼30%). In general, tadpoles were unable to alter the thermal sensitivity of physiological processes, although DTFs induced plasticity in metabolic enzyme activity in all species, although to a greater extent in species from less thermally variable environments. DTFs increased upper thermal limits...

... to estimate enzyme activity do not differentiate between enzymes secreted by the cultivated fungus or associated microbial biofilms. The metabolic activities of fungus gardens are likely quite diverse ( Aylward et al., 2012a ; Aylward et al., 2012b ). Yeasts inhabiting the garden may be important...

... climate change. * These authors contributed equally to this work † Author for correspondence ( anttila@zoology.ubc.ca ) 25 9 2012 2 12 2012 © 2013. Published by The Company of Biologists Ltd 2013 critical maximum temperature enzyme activity heat shock protein...

... Disrupter 100, Gardiner, NY, USA). The suspension was centrifuged at 1700 g for 5 min (4°C) and the protein concentration of the supernatant was then determined ( Bradford, 1976 ). The supernatant was used for enzyme activity measurements and the pellet for MHC isoform content analysis. Enzyme...

... of the minimum, what metabolic pathway is employed? To answer those questions, enzyme activities were used as proxies for the activity of metabolic pathways. Lactate dehydrogenase (LDH) was used as a proxy for glycolytic activity; citrate synthase (CS) was used for Krebs’ cycle activity; malate dehydrogenase...

... enzyme activities. This study confirms the presence of both fast-twitch fibres and high oxidative capacity in black wildebeest, indicating an animal that can run very fast but is also fatigue resistant. * Author for correspondence ( ta.kohn@uct.ac.za ) 11 9 2011 © 2011. 2011 fibre...

... activities. The initial rapid decrease in M. amazonicum gill Na + /K + -ATPase activity after 1 to 5 h of exposure to 25‰ S might result from a direct modulation of enzyme activity by substrate and ions, from increased hemolymph osmolality ( Onken, 1996 ) and/or from hormonally regulated phosphorylation...

... refinement, may prove useful as an in situ indicator of P-stress in aquatic consumers. * Author for correspondence ( paulfrost@trentu.ca ) 6 10 2009 © 2010. ecological stoichiometry enzyme activity nutrition freshwater zooplankton cladoceran The phosphorus (P) content...

... respond similarly during ontogenetic growth of striped bass. Mass-specific metabolic enzyme activity confirmed that glycolytic capacity scaled positively in deep white muscle (regression slope, b =0.1 to 0.8) over a body mass range of ∼20–1500 g, but only creatine phosphokinase showed positive scaling...

... conditions. Moreover, elevation of GSase activities in fore-, mid- and hindbrain in response to environmental ammonia underlines the importance of brain GSase in the ammonia-stress response. ammonia toxicity liver enzyme activity gene expression mRNA nitrogen metabolism glutamine sublethal ammonia...

... evolution between HK activity and mass-specific metabolic rate. Although other enzymes scale allometrically with respect to body mass, e.g. trehalase, glycogen phosphorylase and citrate synthase, no other enzyme activities were correlated with metabolic rate after controlling for phylogenetic relatedness...

... of control (without substrate) and after substrate addition were used to estimate maximal enzyme activity. Iliofibularis muscle samples from the left leg of T. psamonastes, T. itambere and T. oreadicus were collected when animals were killed for the muscle mechanics experiments. Muscle samples were...

...Amanda L. Southwood; Charles A. Darveau; David R. Jones SUMMARY We measured activity levels, oxygen consumption, metabolic enzyme activity,breathing frequency, heart rate and blood chemistry variables of juvenile green turtles exposed to a laboratory simulation of subtropical winter and summer...

... to the new temperature was required to attain a degree of thermal compensation. * Author for correspondence (e-mail: helga.guderley@bio.ulaval.ca ) 2 7 2003 © The Company of Biologists Limited 2003 2003 mitochondria thermal acclimation oxidative muscle enzyme activity thermal...

...) for analysis of metabolic enzyme activity (lactate dehydrogenase, citrate synthase and cytochrome c oxidase). There were significant differences in mean daily body temperatures between winter (15.66±0.43°C; mean ± S.E.M.) and summer(29.34±0.21°C), and daily body temperatures fluctuated significantly more...

... among muscles. © The Company of Biologists Limited 2003 2003 triceps brachii vastus lateralis enzyme activity fat mass exercise muscle oxygen uptake Interestingly, we observed an increased plasma insulin concentration at rest and an increased insulin resistance after the subjects...