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At least 91 records · Page 5Linked to original sources
PubMed1982

The role of metabolism in the control of cyclic AMP efflux, cyclic AMP content, and insulin secretion from rat islets of Langerhans.

Glucose, alpha-ketoisocaproate, and N-acetylglucosamine all initiate insulin release and stimulate cyclic AMP efflux and cyclic AMP accumulation. Mannoheptulose inhibited these islet responses to glucose but not to N-acetylglucosamine or alpha-ketoisocaproate. On the other hand, menadione inhibited these responses to all three secretagogues. Nicotinamide enhanced the insulin release due to glucose and alpha-ketoisocaproate and also enhanced cyclic AMP efflux and intracellular cyclic AMP accumulation. N-acetylglucosamine-mediated insulin release, cyclic AMP efflux, and cyclic AMP accumulation were unaffected by nicotinamide. These results suggest that the metabolic state of the islet is a primary determinant of the ability of a secretagogue to raise cyclic AMP efflux and intracellular cyclic AMP, and these actions may be mediated in part by alterations in the redox state of the pyridine nucleotide system.

Acetylglucosamine↗
PubMed1977

Activation of rat erythrocyte phosphofructokinase by AMP and by non-physiological concentrations of cyclic AMP.

Cyclic AMP (300 micron) activates phosphofructokinase from dialyzed haemolysates of mature rat erythrocytes. The main conclusions are: a) Cyclic AMP, at pH 7.1 and low concentrations of fructose-6-phosphate, is able to reverse the inhibition produced by different amounts of ATP (up to 1.5 mM). b) The cyclic nucleotide is a positive allosteric effector of the enzyme as shown by the displacement of sigmoidal fructose-6-phosphate saturation curve to hyperbolic kinetics in the presence of inhibitory concentrations (1.5 mM) of ATP.c) Cyclic AMP has no significant influence as deinhibitor of phosphofructokinase either at pH 7.1 and non-inhibitory levels (0.25 mM) of ATP or at pH 8.1 and inhibitory (1.5 mM) or non-inhibitory (0.25 mM) concentrations of ATP. Similar conclusions were obtained with 300 micron AMP but not at a lower concentration (3 micron) with both nucleotides. The comparison of cyclic AMP result with those obtained under similar concentrations of AMP suggest that cyclic AMP is really only an "in vitro" modulator of the enzyme from rat erythrocytes, presumably at an AMP regulatory stie, since non-physiological concentrations are required to act as deinhibitor.

Adenosine Monophosphate↗
PubMed1998

Alpha2-adrenoceptor-mediated contractions of the porcine isolated ear artery: evidence for a cyclic AMP-dependent and a cyclic AMP-independent mechanism.

1. The aim of this study was to determine the conditions under which the alpha2-adrenoceptor agonist UK14304 produces vasoconstriction in the porcine isolated ear artery. 2. UK14304 (0.3 microM) produced a small contraction of porcine isolated ear arteries which was 7.8+/-3.3% of the response to 60 mM KCl. Similar sized contractions were obtained after precontraction with either 30 nM angiotensin II, or 0.1 microM U46619 (8.2+/-1.8% and 10.2+/-2.6% of 60 mM KCl response, respectively). However, an enhanced alpha2-adrenoceptor response was uncovered if the tissue was precontracted with U46619, and relaxed back to baseline with 1-2 microM forskolin before the addition of UK14304 (46.9+/-9.6% of 60 mM KCl response). 3. The enhanced responses to UK14304 in the presence of U46619 and forskolin were not inhibited by the alpha1-adrenoceptor antagonist prazosin (0.1 microM), but were inhibited by the alpha2-adrenoceptor antagonist rauwolscine (1 microM), indicating that the enhanced responses were mediated via postjunctional alpha2-adrenoceptors. 4. In the presence of 0.1 microM U46619 and 1 mM isobutylmethylxanthine (IBMX), 1 microM forskolin produced an increase in [3H]-cyclic AMP levels in porcine isolated ear arteries. Addition of 0.3 microM UK14304 prevented this increase. 5. The enhanced UK14304 response was dependent upon the agent used to relax the tissue. After relaxation of ear arteries precontracted with 10 nM U46619 and relaxed with forskolin the UK14304 response was 46.9+/-9.6% of the 60 mM KCl response, and after relaxation with sodium nitroprusside (SNP) the response was 24.8+3.3%. However, after relaxation of the tissue with levcromakalim the UK14304 response was only 8.2+/-1.7%, which was not different from the control response in the same tissues (12.2+/-5.6%). An enhanced contraction was also obtained after relaxation of the tissue with the cyclic AMP analogue dibutyryl cyclic AMP (23.2+/-1.3%) indicating that at least part of the enhanced response to UK14304 is independent of the ability of the agonist to inhibit cyclic AMP production. 6. Relaxation of U46619 contracted ear arteries with SNP could be inhibited by the NO-sensitive guanylyl-cyclase inhibitor 1H-[1,2,4] oxadiazolo[4,3-a]quinoxalin-1-one (ODQ) indicating that production of cyclic GMP is necessary for the relaxant effect of SNP. However, ODQ had no effect on the relaxation of tissue by forskolin, suggesting that this compound does not act via production of cyclic GMP. Biochemical studies showed that while forskolin increases the levels of cyclic AMP in the tissues, SNP had no effect on the levels of this cyclic nucleotide. 7. In conclusion, enhanced contractions to the alpha2-adrenoceptor agonist UK14304 can be uncovered in porcine isolated ear arteries by precontracting the tissue with U46619, followed by relaxation back to baseline with forskolin, SNP or dibutyryl cyclic AMP before addition of UK14304. There was a greater contractile response to UK14304 after relaxation with forskolin than with SNP or dibutyryl cyclic AMP, suggesting that cyclic AMP-dependent and- independent mechanisms are involved in the enhancement of the UK14304 response.

15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5↗
PubMed2001

The relationship between AMP-activated protein kinase activity and AMP concentration in the isolated perfused rat heart.

The objective of this study was to define the relationship among AMP-activated protein kinase (AMPK) activity, AMP concentration ([AMP]), and [ATP] in perfused rat hearts. Bromo-octanoate, an inhibitor of beta-oxidation, and amino-oxyacetate, an inhibitor of the malate-aspartate shuttle, were used to modify substrate flux and thus increase cytosolic [AMP]. Cytosolic [AMP] was calculated using metabolites measured by (31)P NMR spectroscopy. Rat hearts were perfused with Krebs-Henseleit solution containing glucose and either no inhibitor, the inhibitors, or the inhibitors plus butyrate, a substrate that bypasses the metabolic blocks. In this way, [AMP] changed from 0.2 to 27.9 microm, and [ATP] varied between 11.7 and 6.8 mm. AMPK activity ranged from 7 to 60 pmol.min(-1).microg of protein(-1). The half-maximal AMPK activation (A(0.5)) was 1.8 +/- 0.3 microm AMP. Measurements in vitro have reported similar AMPK A(0.5) at 0.2 mm ATP, but found that A(0.5) increased 10-20-fold at 4 mm ATP. The low A(0.5) of this study despite a high [ATP] suggests that in vivo the ATP antagonism of AMPK activation is reduced, and/or other factors besides AMP activate AMPK in the heart.

AMP-Activated Protein Kinases↗
PubMed1977

Effects of cyclic AMP and dibutyryl cyclic AMP on cerebral hemodynamics and metabolism in the baboon.

Adenosine 3',5'-cycle monophosphate (cyclic AMP) (0.5 mg/kg) was infused into the carotid artery of baboons anesthesized with sodium pentobarbital, causing a biphasic increase in cerebral blood flow (CBF) and reduction in cerebrovascular resistance (CVR) associated in each phase with stimulation of cerebral metabolism evidenced by increased cerebral oxygen consumption (COMRO2) and cerebral glucose consumption (CMRG1). Intracarotid dibutyryl cyclic AMP (0.5 mg/kg) caused a monophasic increase in CBF and reduction of CVR but failed to alter cerebral metabolism. This may be due to its rapid removal from the circulation with ineffective passage across the blood-brain barrier since intracisternal infusion of dibutyryl cyclic AMP caused sustained increase in CBF, CMRO2 and CMRG1 and reduction in CVR. Intracarotid AMP (0.4 mg/kg) and adenosine (0.3 mg/kg) caused an immediate and more marked increase in CBF and decrease in CVR unassociated with cerebral metabolic change making it unlikely that the observed effects of cyclic AMP can be attributed to its breakdown products. Cyclic AMP or its dibutyryl derivative may alter cerebral metabolism secondary to neuronal activation but increase in glucose/oxygen utilization ratio after intracarotid cyclic AMP and intracisternal dibutytyl cyclic AMP also suggests an influence on enzymatic regulation of glucose metabolism.

Adenosine↗
PubMed1989

ARPP-21, a cyclic AMP-regulated phosphoprotein (Mr = 21,000) enriched in dopamine-innervated brain regions. Amino acid sequence of the site phosphorylated by cyclic AMP in intact cells and kinetic studies of its phosphorylation in vitro.

ARPP-21 (cyclic AMP-regulated phosphoprotein, Mr = 21,000) is a cytosolic neuronal phosphoprotein that is highly enriched in regions of mammalian brain that receive dopaminergic innervation, in particular the striatum. The state of phosphorylation of ARPP-21 in brain slices prepared from rat striatum was shown to be regulated by 8-bromo-cyclic AMP. Phosphorylation occurred exclusively on seryl residues contained within a single tryptic phosphopeptide as analyzed by two-dimensional thin layer electrophoresis/chromatography. The tryptic phosphopeptide derived from ARPP-21 phosphorylated in intact cells comigrated with the tryptic phosphopeptide derived from purified ARPP-21 phosphorylated by the catalytic subunit of cyclic AMP-dependent protein kinase in vitro. Purified cyclic AMP-dependent protein kinase catalyzed the incorporation of 1.1 mol of [32P]phosphate/mol of ARPP-21 exclusively on seryl residues. The amino acid sequence surrounding the site in purified ARPP-21 phosphorylated by cyclic AMP-dependent protein kinase in vitro was determined by analyzing two overlapping chymotryptic peptides isolated from [32P]phospho-ARPP-21 by reverse phase high performance liquid chromatography. A combination of gas phase and solid phase amino acid sequencing yielded a phosphorylation site sequence of -Glu-Arg-Arg-Lys-Ser(P)-Lys-Ser-Gly-Ala-Gly-. Initial rate studies of the phosphorylation of purified ARPP-21 by the catalytic subunit of cyclic AMP-dependent protein kinase yielded an apparent Km of 0.78 microM and a kcat of 2.2 s-1. A synthetic peptide based on the phosphorylation site of ARPP-21 was phosphorylated on the corresponding seryl residue with an apparent Km of 40 microM and a kcat of 4.0 s-1. These results are compatible with a physiological role for the phosphorylation of ARPP-21 by cyclic AMP-dependent protein kinase in vivo, regulated by first messengers acting via cyclic AMP, e.g. dopamine and vasoactive intestinal peptide.

Amino Acid Sequence↗
PubMed1981

Effects of prostaglandin D2 and theophylline on rat serosal mast cells: discordance between increased cellular levels of cyclic AMP and activation of cyclic AMP-dependent protein kinase.

Previous studies have shown that perturbation of the mast cell IgE-Fc receptor activates adenylate cyclase so as to raise cellular levels of cyclic AMP and to activate cyclic AMP-dependent protein kinase. Theophylline, an inhibitor of cytoplasmic cyclic nucleotide phosphodiesterase, raises cellular cyclic AMP levels, activates Type I and Type II cytoplasmic cyclic AMP-dependent protein kinase isoenzymes, and inhibits immunologic mediator release in a dose-dependent fashion. Since the EC50 values for each of these effects are similar (8 to 9.5 mM), it seems likely that a relationship exists between the activation of cyclic AMP-dependent protein kinase and the inhibition of mediator release. Such inhibition could be due to either to the uncovering of an inhibitory protein by phosphorylation or to the depletion of cyclic AMP-dependent protein kinase holoenzyme, which is essential for productive IgE-Fc receptor-induced activation-secretion coupling. PGD2, which also raises mast cell cyclic AMP levels in a dose-dependent fashion and interacts synergistically with theophylline in this regard, fails to suppress mediator release alone or to add to the inhibitory effect of theophylline. The finding that PGD2 also fails to activate cyclic AMP-dependent protein kinase suggests that the adenylate cyclase stimulated by this agonist is not linked to the mast cell activation-secretion response.

Animals↗
PubMed1981

[Cyclic AMP accumulation in psoriatic skin: differential responses to epinephrine, AMP and histamine (author's transl)].

Epidermal adenylate cyclase can be activated independently by epinephrine, adenosine and histamine resulting in the accumulation of cyclic AMP. Using the uninvolved and involved keratome-sliced skin from psoriatic patients, we investigated the effects of these agents in vitro on the intra-cellular cyclic AMP levels of the skin. In the involved skin of psoriasis, epinephrine-induced cyclic AMP accumulation was decreased, whereas no decrease in adenosine- or histamine-induced cyclic AMP accumulation was seen. Since keratome-sliced skin samples had various amounts of dermal contamination, we also investigated the effect of epinephrine on the "pure" epidermal cyclic AMP level. After the incubation with epinephrine, pure epidermal samples, which were micro-dissected free from stratum corneum, dermis and skin appendages, were assayed for cyclic AMP level. Again cyclic AMP accumulation was decreased in the involved skin. Thus epinephrine-induced cyclic AMP accumulation was shown to be decreased in the involved epidermis of psoriasis.

Adenosine Monophosphate↗
PubMed1976

1,N6-etheno-AMP and 1,N6-etheno-2'-deoxy-AMP as probes of the activator site of glycogen phosphorylase from rabbit skeletal muscle.

Both 1,N6-etheno-AMP and 1,N6-etheno-2'-deoxy-AMP bind at the AMP site of phosphorylase b (1,4-alpha-D-glucan:orthophosphate alpha-glucosyltransferase, EC 2.4.1.1). Etheno-AMP induces the same activation as AMP, about 30-fold higher than the activation induced by etheno-dAMP. The fluorescence of etheno-AMP and etheno-dAMP is associated with the base moiety; therefore, when free in solution, the two derivatives have identical fluorescence properties. However, when bound to phosphorylase, the fluorescence of etheno-AMP is quenched more efficiently than the fluorescence of etheno-dAMP. This difference between the fluorescence properties of the bound nucleotides suggests that a modification in the ribose ring affects the position of the adenine in the AMP site of phosphorylase b. The observed quenching may be due to a stacking interaction between an aromatic residue and the base moiety of the bound nucleotide.

Adenosine Monophosphate↗
PubMed1981

Folate deaminase and cyclic AMP phosphodiesterase in Dictyostelium discoideum: their regulation by extracellular cyclic AMP and folic acid.

Cyclic AMP and folic acid act as chemotactic factors in Dictyostelium discoideum. Both agents, when applied extracellularly, also control cell development from the growth stage to the acquisition of aggregation competence. Cyclic AMP phosphodiesterase and folate deaminase are extracellular enzymes whose activity is regulated during early differentiation of D. discoideum cells. The two enzymes help control the extracellular levels of cyclic AMP and folic acid. The substrates cyclic AMP and folic acid each increase the extracellular activity of folate deaminase as well as phosphodiesterase. The specificity of extracellular phosphodiesterase regulation by cyclic AMP indicates that the effect is mediated by specific cyclic AMP receptors rather than the catalytic site of cell surface phosphodiesterase. To some extent cyclic AMP and folic acid are interchangeable with respect to regulating differentiation and enhancing enzymatic inactivation of intercellular signals. Thus the two extracellular signals may share a common cellular pathway of signal transduction. The regulation of folate deaminase and phosphodiesterase by folic acid does not always parallel the folic acid effects on development. Pulses of folic acid stimulate development of aggregation competence, whereas a continuous flux inhibits. In contrast, either continuous flux or pulses of folic acid increase the deaminase and phosphodiesterase activities.

3',5'-Cyclic-AMP Phosphodiesterases↗
PubMed1980

Insulin trigger, cyclic AMP-dependent activation and phosphorylation of a plasma membrane cyclic AMP phosphodiesterase.

Regulation of blood glucose levels by the liver is primarily achieved by the action of two peptide hormones, insulin and glucagon, which bind to specific receptors associated with the hepatocyte plasma membrane. Whilst the molecular action of glucagon at the level of the cell plasma membrane in activating adenylate cyclase is relatively well understood, we know little, if anything, of the molecular consequences of insulin occupying its receptor. We demonstrate here that insulin, at physiologically relevant concentrations, can trigger the cyclic AMP-dependent activation and phosphorylation of a low Km cyclic AMP phosphodiesterase attached to the liver plasma membrane. Such an effect may in part explain the ability of insulin to inhibit the increase in cellular cyclic AMP content that glucagon alone produces by activation of adenylate cyclase. Our observation that basal, intracellular cyclic AMP levels are insufficient to allow insulin to activate the cyclic AMP phosphodiesterase, yet those cyclic AMP levels achieved after exposure of the cells to glucagon are sufficient, gives a molecular rationale to Butcher and Sutherland's proposal that it is necessary to first elevate cellular cyclic AMP levels before they can be depressed by insulin.

3',5'-Cyclic-AMP Phosphodiesterases↗
PubMed1985

Positive regulation of the colicin E1 gene by cyclic AMP and cyclic AMP receptor protein.

In previous experiments, we showed that the in vivo transcription of the colicin E1 gene was dependent on cyclic AMP in adenylate cyclase-defective mutant cells of Escherichia coli (Ebina, Y. and Nakazawa, A (1983) J. Biol. Chem. 258, 7072-7078). We now show that cyclic AMP and cyclic AMP receptor protein stimulated the in vitro transcription of the gene in the presence of spermidine. As determined in DNase I protection experiments, two binding sites for the complex of cyclic AMP and the receptor protein were identified about 60 base pairs (CRP-1) and 110 base pairs (CRP-2) upstream from the transcription initiation site of the colicin E1 gene. CRP-1 had a higher affinity for the complex than that of CRP-2. Substituting an unrelated DNA sequence for CRP-2 reduced the efficiency of in vitro stimulation of the gene by cyclic AMP and the receptor protein. These potential binding sites for the cyclic AMP-cyclic AMP receptor protein complex probably participate in the stimulation of the colicin E1 gene transcription.

Base Sequence↗
PubMed1978

Cyclic AMP binding proteins and cyclic AMP-dependent protein kinase from Blastocladiella emersonii.

The stoichiometry of cyclic AMP binding protein to cyclic AMP in sporulating cells of Blastocladiella emersonii and the resistance of protein-bound cyclic AMP to enzyme-catalyzed hydrolysis suggest that the distribution of cyclic AMP between free and protein-bound pools is an important factor in cyclic AMP metabolism. Most but not all of the cyclic AMP binding protein in sporulating cells is associated with a cyclic AMP-dependent protein kinase.

3',5'-Cyclic-AMP Phosphodiesterases↗
PubMed1992

Positive and negative control of ompB transcription in Escherichia coli by cyclic AMP and the cyclic AMP receptor protein.

The ompB operon encodes OmpR and EnvZ, two proteins that are necessary for the expression and osmoregulation of the OmpF and OmpC porins in Escherichia coli. We have used in vitro and in vivo experiments to show that cyclic AMP and the cyclic AMP receptor protein (CRP) directly regulate ompB. ompB expression in an ompB-lacZ chromosomal fusion strain was increased two- to fivefold when cells were grown in medium containing poor carbon sources or with added cyclic AMP. In vivo primer extension analysis indicated that this control is complex and involves both positive and negative effects by cyclic AMP-CRP on multiple ompB promoters. In vitro footprinting showed that cyclic AMP-CRP binds to a 34-bp site centered at -53 and at -75 in relation to the start sites of the major transcripts that are inhibited and activated, respectively, by this complex. Site-directed mutagenesis of the crp binding site provided evidence that this site is necessary for the in vivo regulation of ompB expression by cyclic AMP. Control of the ompB operon by cyclic AMP-CRP may account for the observed regulation of the formation of OmpF and OmpC by this complex (N. W. Scott and C. R. Harwood, FEMS Microbiol. Lett. 9:95-98, 1980).

Bacterial Outer Membrane Proteins↗
PubMed1986

Cyclic AMP, adenylate cyclase and cyclic AMP-phosphodiesterase activities in diabetic rat adipocytes.

The effect of streptozotocin-induced diabetes on cyclic AMP content, adenylate cyclase and cyclic-AMP phosphodiesterase activities in rat adipocytes was investigated. The results show that diabetes induced an increase in intracellular cyclic AMP. Basal adenylate cyclase activity and in response to norepinephrine were higher in fat cell membranes from diabetic rats. Adenylate cyclase activity stimulated by fluoride was the same in both normal and diabetic preparations. Low and high Km phosphodiesterase activities in adipocytes from diabetic rats were higher than the controls. The results suggest that the deficiency of insulin present in the diabetic state induces an increase in adenylate cyclase activity which increases the cyclic AMP production. This increase in cyclic AMP promotes a higher cyclic AMP-phosphodiesterase activity which is not sufficient to hydrolyze all the newly formed cyclic AMP.

3',5'-Cyclic-AMP Phosphodiesterases↗
PubMedDate not supplied

The regulation of cyclic AMP production and the role of cyclic AMP in B16 melanoma cells of differing metastatic potential.

The nature of the relationship between agonist-stimulated cyclic AMP production and metastatic potential was examined in detail for four B16 melanoma cell lines of varying metastatic potential. Highly metastatic cells (B16 F10C1) appeared to differ from cells of low metastatic potential (B16 F1C29) in the degree to which cyclic AMP production in intact cells was stimulated by protein kinase C activation. No significant difference was found in the adenylate-cyclase enzyme activities of the broken cells, irrespective of the agonist used, or in the distribution of cyclic AMP between the intracellular and extracellular compartment. Although B16F1, F10 and F10C1 cells all produced equally pigmented tumors in vivo, the cells differed in their melanogenic response to cyclic AMP elevating agents in vitro: the least metastatic cells produced least agonist-induced cyclic AMP but this induced greatest tyrosinase activation and melanin production in vitro; conversely, the more metastatic cells produced more cyclic AMP but less tyrosinase activation and melanin production in response to agonist stimulation. Thus, agonist-stimulated cyclic AMP production does not appear to be coupled to the differentiated function of melanogenesis for highly metastatic B16 melanoma cells.

Adenylyl Cyclases↗
PubMed1979

Interaction of rat muscle AMP deaminase with myosin. I. Biochemical study of the interaction of AMP deaminase and myosin in rat muscle.

AMP deaminase was completely solubilized from rat skeletal muscle with 50 mM Tris-HCl buffer (pH 7.0) containing KCl at a concentration of 0.3 M or more. The purified enzyme was found to be bound to rat muscle myosin or actomyosin, but not to F-actin at KCl concentrations of less than 0.3 M. Kinetic analysis indicated that 1 mol of AMP deaminase was bound to 3 mol of myosin and that the dissociation constant (Kd) of this binding was 0.06 micrometer. It was also shown that AMP deaminase from muscle interacted mainly with the light meromyosin portion of the myosin molecule. This finding differs from that of Ashby and coworkers on rabbit muscle AMP deaminase, probably due to a difference in the properties of rat and rabbit muscle AMP deaminase. AMP deaminase isozymes from rat liver, kidney and cardiac muscle did not interact with rat muscle myosin. The physiological significance of this binding of AMP deaminase to myosin is discussed.

AMP Deaminase↗
PubMed1992

Regional variations in particulate cyclic AMP dependent-protein kinase binding activity in the gerbil hippocampus following transient forebrain ischemia by [3H]cyclic AMP binding.

Changes in the binding of [3H]cyclic AMP as an indicator of particulate cyclic AMP-dependent protein kinase (AMP-DPK) binding activity following transient forebrain ischemia were studied in the gerbil using in vitro autoradiography. [3H]Cyclic AMP binding in the strata pyramidale and lacunosum-moleculare of the hippocampal CA1, the stratum pyramidale of the CA3, and the dentate gyrus decreased transiently in the early postischemic phase but then recovered. However, [3H]cyclic AMP binding in the strata pyramidale and radiatum of the CA1, the granular layer of the dentate gyrus, and the upper layer of the cortex decreased again 7 days after ischemia. In the CA4 subfield and the lower layer of the cortex, the binding showed no significant alterations after ischemia. Administration of pentobarbital prior to the induction of ischemia prevented the decrease in [3H]cyclic AMP binding in the CA1 subfield 6 h and 7 days after ischemia, and showed protective effects against neuronal death of the CA1 pyramidal cells 7 days after ischemia. These results indicate that marked alteration of intracellular signal transduction precedes neuronal damage in the hippocampal CA1 subfield. Furthermore, postischemic reduction of [3H]cyclic AMP binding in the histologically intact cerebral cortex, CA3, and dentate gyrus may be the reflection of cellular dysfunction after energy failure.

Animals↗