.... Mitochondria produce ∼90% of the ATP required by cells to maintain cellular integrity and function. They also integrate into biosynthetic pathways that support metabolism as a whole, allow communication within the cell, and regulate cellular health and death pathways. We have previously shown that cardiac...

... tolerance involves the ability to maintain cellular ATP despite the loss of aerobic metabolism. However, insects such as adult Drosophila melanogaster are able to survive long periods of anoxia (LT 50 : ∼8 h) in a hypo-energetic state characterized by low [ATP]. In this study, we tested for possible...

... of compounds (e.g. salts, amino acids, vitamins, nucleotides, cholesterol and fatty acids) in these bioassays. ATP was the most effective phagostimulant in adults and nymphs, resulting in >70% of bed bugs fully engorging. Addition of NaCl to low ATP solutions that alone elicited <50% engorgement...

... effector, ATP, permitting detailed assessment of overall oxygenation enthalpies (ΔH′) and contributions from oxygenation-linked proton and ATP dissociation. Billfish express multiple isohemoglobins with similar O 2 affinities and pronounced sensitivities to pH and ATP. Compared with the moderate effects...

...-dependent release of ATP from RBCs, which stimulates production of nitric oxide (NO) and other vasodilators in the endothelium; (2) release of vasoactive NO from S -nitroso-Hb upon deoxygenation; and (3) reduction of naturally occurring nitrite to vasoactive NO by deoxygenated Hb. This Commentary inspects...

... at high concentrations. The effects of 5-HT were blocked by methysergide. In the prometamorphic tadpole, ATP elicited relaxation that was blocked by the ectonucleotidase inhibitor ARL67156 and the adenosine A 1 receptor antagonist 1,3-dipropyl-8-cyclopentylxanthine (DPCPX), suggesting adenosine...

... with dinitrophenol (0.5 mmol l –1 ) increased the gap-junction resistance 66-fold,suggesting the regulation of gap junctions by ATP. Lucifer Yellow injected into a principal cell did not appear in neighboring principal cells. Thus, gap junctions allow the passage of current but not Lucifer Yellow. Using RT-PCR we...

...Daniel S. Wu; Klaus W. Beyenbach SUMMARY The relationship between the intracellular ATP concentration[ATP] i and the electrical properties of principal cells was investigated in Malpighian tubules of the yellow fever mosquito, Aedes aegypti . Under control conditions, [ATP] i was 0.91 mmol l -1...

... of tissues we tested ATP and adenosine for their effects on epithelial transport. Examination of integuments from pondwater- and high-salinity-adapted leeches revealed different sensitivities for these purines. Apical and basolateral application of ATP both stimulated transepithelial Na + uptake and I ami...

...Debra L. Knickerbocker; Peter L. Lutz SUMMARY For most vertebrates, cutting off the oxygen supply to the brain results in a rapid (within minutes) loss of ATP, the failure of ATP-dependent ion-transport process, subsequent anoxic depolarization of neuronal membrane potential and consequential...

... sulfide in gill mitochondria. Well-coupled mitochondria isolated from G. demissa gills were used to investigate sulfide oxidation and ATP synthesis. State 3 respiration, maximally stimulated by 5 μ mol l −1 sulfide with a P/O ratio of 0.89 and a respiratory control ratio (RCR) of 1.40, remained refractory...

...Stefanie Dragon; Cynthia Carey; Kathy Martin; Rosemarie Baumann ABSTRACT In chick embryos, developmental changes of the blood oxygen tension control hemoglobin (Hb) oxygen affinity via modulation of ATP and 2,3BPG concentrations in red blood cells. Hypoxia, which is a normal developmental condition...

... to anoxia at 25 °C, there is an immediate fall in brain ATP levels, which reach approximately 20 % of normoxic levels in approximately 60 min. The frog, nevertheless, survives another 1–2 h of anoxia. At 100 min of anoxia, there is an increase in extracellular adenosine concentration, probably originating...

... gradients did not affect vesicular Mg 2+ transport in apical and basolateral membrane preparations, suggesting the presence of an ion-coupled transport mechanism. ATP or ATP-γ-S did not stimulate Mg 2+ fluxes, indicating that Mg 2+ transport does not proceed via an ATP-driven or activated transporter...

...Rolf L. Ingermann; David C. Bencic; Jay K. Herman ABSTRACT Nucleated red cells in the nonpregnant garter snake ( Thamnophis elegans ) contain relatively high concentrations of nucleoside triphosphate (NTP), largely in the form of ATP, which is found at concentrations of approximately 10 mmol l − 1...

... to temperature-induced changes in intracellular diffusion coefficients ( D ) of the high-energy phosphate compounds ATP and creatine phosphate (PCr). Using 31 P nuclear magnetic resonance spectroscopy, we determined D PCr and D ATP in goldfish ( Carassius auratus ) skeletal muscle at 25 °C and 5 °C: D PCr...

...F. J. Sartoris; H. O. Pörtner ABSTRACT The effects of temperature (0, 5, 10, 15 and 20 °C) and of anoxia (at 5 °C) on extracellular Mg 2+ concentration ([Mg 2+ ] e ), intracellular pH (pHi) and ATP and lactate levels were investigated in intermoult adults of the common shrimp Crangon crangon . All...

...Werner A. Wuttke; Thomas Munsch; Joachim W. Deitmer ABSTRACT The effects of extracellular ATP on intracellular free Ca 2+ concentration ([Ca 2+ ] i ) and depolarization-induced elevations of [Ca 2+ ] i were investigated in salivary cells of the leech Haementeria ghilianii using the fluorescent Ca 2...

... acidosis (elevated CO 2 levels under aerobic conditions). During 6 h of recovery from anoxia, the levels of ubiquitin-conjugated proteins rose 6.5-fold, reaching 78 % of the pre-anoxia (control) values. Concomitant with the elevation in ubiquitin conjugates was a sharp decline in AMP level, a rise in ATP...

... of adenosine and guanosine was observed in hypoxic animals. Similarly, a decrease in both ATP and GTP levels occurred in hypoxic animals injected either with saline or with carbonic anhydrase. Interestingly, there was a highly significant relationship between ATP and GTP levels, indicating that they are under...