THE ROLE OF LACTATE IN THE STIMULATION OF THE OXYGEN CONSUMPTION OF FROG MUSCLE BY INSULIN

1964 ◽  
Vol 42 (1) ◽  
pp. 139-151 ◽  
Author(s):  
D. R. H. Gourley ◽  
Kenneth C. Fisher
Keyword(s):  
Oxygen Consumption ◽  
Major Effect ◽  
Ringer Solution ◽  
Frog Muscle ◽  
Complete Oxidation ◽  
Rate Of Oxygen Consumption ◽  
Lactate Utilization ◽  
Stimulation Of ◽  
Extra Oxygen

Lactate, citrate, succinate, or acetate added to isolated muscles suspended in Ringer solution in a Warburg flask produced an increase in the rate of oxygen consumption by the muscles. At a given molar concentration of these substances the increase was greatest with lactate and was progressively less with the addenda in the order given. When the concentration of each substance was adjusted so that the rate of oxygen consumption was the same with all of them, the addition of insulin produced an increase in the oxygen uptake which was of the same magnitude in each case. Evidence is presented which suggests that by causing spontaneous activity in the muscle, the acetate, succinate, and citrate may bring about a production of lactate.The extra oxygen consumed upon the addition of lactate could account for the complete oxidation of only a small part of the lactate which actually disappeared in an experiment. By assuming that all of this extra oxygen was used in the complete oxidation of lactate, it was calculated from the total lactate utilization in the presence or absence of insulin that the major effect of insulin was on the fraction of utilized lactate which was oxidized. This conclusion was also suggested by experiments with monoiodoacetate.

Stimulation of Oxygen Consumption by Insulin in Intact Isolated Frog Muscle

1954 ◽  
Vol 179 (1) ◽  
pp. 29-35 ◽  
Author(s):  
James C. Hall ◽  
Kenneth C. Fisher ◽  
Joseph R. Stern
Keyword(s):  
Oxygen Consumption ◽  
Frog Muscle ◽  
Stimulation Of

scholarly journals Stimulation of Oxygen Consumption with Fluid Absorption in Insect Recta

1982 ◽  
Vol 101 (1) ◽  
pp. 233-254
Author(s):  
D.F. HOULIHAN ◽  
D. SELL
Keyword(s):  
Oxygen Consumption ◽  
Time Course ◽  
Fluid Injection ◽  
Fluid Absorption ◽  
Fluid Uptake ◽  
Local Osmosis ◽  
Before And After ◽  
Rate Of Oxygen Consumption ◽  
Stimulation Of

The oxygen consumption of excised abdomens of cockroaches and locusts has been measured before and after the injection of fluids into the ligated recta. Fluid injection caused a transient stimulation of oxygen consumption of up to 30% of the resting rate. The extra amount of oxygen consumed is positively correlated with the osmolality of the fluid injected and the amount of fluid absorbed. Parallel experiments were carried out on the time course of fluid uptake; these experiments revealed a correlation first between a rapid increase in fluid absorption and stimulation of oxygen consumption, and secondly between the final resting rate of oxygen consumption and a slower absorption of fluid. Locusts take up fluid at double the rate of cockroaches and have double the stimulation in oxygen consumption following fluid injection. In locusts the increases in oxygen consumption can also be correlated with the net movement of Na+, K+and Cl− from the rectum. The stimulation of oxygen consumption during fluid uptake is discussed in relation to the local osmosis model for fluid uptake.

Release of creatine kinase from frog muscle by osmotic changes

1982 ◽  
Vol 242 (5) ◽  
pp. C398-C403 ◽  
Author(s):  
G. Suarez-Kurtz
Keyword(s):  
Creatine Kinase ◽  
Release Rate ◽  
Ringer Solution ◽  
Step Change ◽  
Frog Muscle ◽  
Base Line ◽  
Irreversible Loss ◽  
Glycerol Treatment ◽  
Tubular Membranes ◽  
Stimulation Of

The rate of creatine kinase (CK) release from isolated frog extensor longus digiti IV (,toe”) muscle increased on transfer from the control Ringer solution (referred to as 1.0 T) to a hyperosmotic solution (1.0 T plus 400 mM glycerol) or to hypertonic solutions (1.5–2.5 T) prepared by addition of NaCl or sucrose to 1.0 T. On return to 1.0 T, CK release rate was further elevated, reaching peak values (14.4- and 12-fold above the basal value, respectively, with the glycerol treatment and with solution 2.5 T) within 10–15 min and declining subsequently toward base line. Although the stimulation of CK release by changes in external tonicity increased with the magnitude of the osmotic step change, there was no enhancement of release when the tonicity changes were performed gradually in 0.1-T steps at 1-min intervals. The stimulation of CK release by tonicity changes cannot be ascribed to irreversible loss of functional integrity of the surface or tubular membranes or to CK diffusion through aqueous pores. The possibility that an exocytosislike process is involved is discussed.

Relationship between motility and oxygen consumption of sperm from the cauda epididymides of the rat

1999 ◽  
Vol 11 (2) ◽  
pp. 87 ◽  
Author(s):  
R. N. Murdoch ◽  
R. C. Jones ◽  
V. L. Armstrong ◽  
J. Clulow
Keyword(s):  
Oxygen Consumption ◽  
Respiration Rate ◽  
Sperm Motility ◽  
Dibutyryl Camp ◽  
Epididymal Sperm ◽  
Exogenous Substrate ◽  
Individual Effects ◽  
Rate Of Oxygen Consumption ◽  
Stimulation Of

The oxygen consumption of rat sperm was low (2.7 µL O2 108 sperm–1h–1) in caudal epidi-dymal semen (CES) when stimulation of motility was avoided. The addition of 1 µL of Krebs Ringer phosphate buffer (KRP) to 40 µL of CES (CES : KRP = 40 : 1) did not activate motility, but stimulated oxygen consumption 2-fold. Inclusion of 1–5 mМ glucose, acetate, pyruvate or lactate in the KRP further stimulated respiration rate (up to 4.3-fold) without activating motility, but respiration was reduced when 2- deoxyglucose replaced energy substrates. Inclusion of dibutyryl cAMP (1 mM) activated sperm motility in all samples and stimulated oxygen consumption 2.9-fold. Dilution of CES at the ratio of CES : KRP = 40 : 1000 also activated sperm motility and stimulated respiration rate 2.9-fold. The combined effect of dibutyryl cAMP and glucose in stimulating respiration was greater than their individual effects. However, the response to cAMP or substrates was not altered by incubation in KRP containing either 0 or 0.5 mM Ca2+. It was concluded that the motility and metabolism of rat epididymal sperm are suppressed in vivo. Respiration can be stimulated by a small (1.025-fold) dilution and further stimulated by the inclusion of energy substrate, without activating motility. However, a larger dilution or inclusion of cAMP activated motility and simultaneously stimulated metabolism, with exogenous substrate being required to stimulate respiration to the maximum rate. This suggests that prior to activation, the rate of oxygen consumption and sperm motility are not coupled.

gp91phox-containing NAD(P)H oxidase mediates attenuation of nitric oxide-dependent control of myocardial oxygen consumption by ANG II

2005 ◽  
Vol 289 (2) ◽  
pp. H862-H867 ◽  
Author(s):  
Shintaro Kinugawa ◽  
Juhua Zhang ◽  
Eric Messina ◽  
Erin Walsh ◽  
Harer Huang ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Oxygen Consumption ◽  
Myocardial Oxygen Consumption ◽  
Inflammatory Cells ◽  
Oxygen Electrode ◽  
No Production ◽  
Ang Ii ◽  
Wild Type ◽  
Stimulation Of

We have previously reported that ANG II stimulation increased superoxide anion (O2−) through the activation of NAD(P)H oxidase and inhibited nitric oxide (NO)-dependent control of myocardial oxygen consumption (MV̇o2) by scavenging NO. Our objective was to investigate the role of NAD(P)H oxidase, especially the gp91phox subunit, in the NO-dependent control of MV̇o2. MV̇o2 in mice with defects in the expression of gp91phox [gp91phox(−/−)] was measured with a Clark-type oxygen electrode. Baseline MV̇o2 was not significantly different between wild-type (WT) and gp91phox(−/−) mice. Stimulation of NO production by bradykinin (BK) induced significant decreases in MV̇o2 in WT mice. BK-induced reduction in MV̇o2 was enhanced in gp91phox(−/−) mice. BK-induced reduction in MV̇o2 in WT mice was attenuated by 10−8 mol/l ANG II, which was restored by coincubation with Tiron or apocynin. In contrast to WT mice, BK-induced reduction in MV̇o2 in gp91phox(−/−) mice was not altered by ANG II. There was a decrease in lucigenin (5 × 10−6 mol/l)-detectable O2− in gp91phox(−/−) mice compared with WT mice. ANG II resulted in significant increases in O2− production in WT mice, which was inhibited by coincubation with Tiron or apocynin. However, ANG II had no effect on O2− production in gp91phox(−/−) mice. Histological examination showed that the development of abscesses and/or the invasion of inflammatory cells occurred in lungs and livers but not in hearts and kidneys from gp91phox(−/−) mice. These results indicate that the gp91phox subunit of NAD(P)H oxidase mediates O2− production through the activation of NAD(P)H oxidase and attenuation of NO-dependent control of MV̇o2 by ANG II.

Cytosolic calcium, oxygen consumption and the intracellular pH of stimulated neutrophils

1988 ◽  
Vol 8 (1) ◽  
pp. 65-76 ◽  
Author(s):  
Patricia E. Nasmith ◽  
Sergio Grinstein
Keyword(s):  
Oxygen Consumption ◽  
Intracellular Ph ◽  
Cytosolic Calcium ◽  
Cytoplasmic Ph ◽  
Acid Generation ◽  
Cytoplasmic Acidification ◽  
Free Media ◽  
Stimulation Of

The cytoplasmic pH undergoes a biphasic change when neutrophils are activated. The role of Ca2+ in initiating these changes was investigated. No correlation was found between the increased cytosolic [Ca2+] and the stimulation of the Na+/H+ antiport. Similarly, the cytoplasmic acidification elicited by activation in Na+-free media was found to be unrelated to [Ca2+]. Reversal of Na+/H+ exchange was also ruled out as the source of the acidification. Data using a variety of soluble activators indicate that metabolic acid generation is largely responsible for the observed drop in cytoplasmic pH.

scholarly journals STUDIES ON CELL METABOLISM AND CELL DIVISION

1936 ◽  
Vol 20 (2) ◽  
pp. 173-184 ◽  
Author(s):  
M. E. Krahl ◽  
G. H. A. Clowes
Keyword(s):  
Oxygen Consumption ◽  
Cell Division ◽  
Cell Metabolism ◽  
Substituted Phenols ◽  
Experimental Conditions ◽  
Arbacia Punctulata ◽  
Oxidation Reduction ◽  
Rate Of Oxygen Consumption ◽  
Considerable Support ◽  
Stimulation Of

The dihalo and trihalophenols, and phenols containing both halo and nitro substituents in the same molecule, produce, in fertilized eggs of Arbacia punctulata, a rise in rate of oxygen consumption and a reversible block to cell division. To define the conditions which affect the degree of this activity, the following factors have been varied: the arrangement of substituents in the molecule, the concentration of reagent, and the time after fertilization at which the reagent is added. The stimulation of oxygen consumption and reversible block to cell division produced by the dihalophenols are qualitatively the same as those previously produced in fertilized Arbacia eggs by certain dinitrophenols. To yield optimum respiratory effect and maximum division block, it usually requires a higher concentration of dihalo than of the corresponding dinitrophenol. For example, with fertilized Arbacia eggs at 20°C. 2,4-dinitrophenol, in optimum concentration of 3 x 10–5 molar, raises oxygen consumption to 292 per cent of normal (4). The corresponding values for two dihalo analogues are: 2,4-dichlorophenol, 10–4 molar and 236 per cent; 2,4-dibromophenol, 6 x 10–5 molar and 282 per cent. The halophenols differ from the nitrophenols in two interesting respects: (a) The monohalophenols produce little or no oxidative stimulation or division block in fertilized Arbacia eggs; p-nitrophenol is very active in both respects. (b) The symmetrical trihalophenols have an appreciable ability to stimulate oxygen consumption and block division; symmetrical trinitrophenol is inactive in both respects (4). The increases in oxygen consumption produced in fertilized Arbacia eggs by 2,4-dichloro and 2,4-dinitrophenol are larger than the percentage increases given by methylene blue and o-cresol indophenol under the same experimental conditions. The dihalo and dinitrophenols produce a reversible block to the cell division of fertilized marine eggs. The oxidation-reduction indicators, in contrast to the dihalo and dinitrophenols, block cell division irreversibly and fertilized eggs of Arbacia do not recover from optimum respiratory stimulating concentrations of these oxidation-reduction dyes. The present experiments with halophenols are in harmony with and lend considerable support to the hypothesis (4) that nitro and similarly substituted phenols derive their biological activity from the presence and properties of the phenolic OH group, as modified by proper substitution in the phenolic benzene ring.

Constant-pressure perfusion of rat hindlimb shows alpha- and beta-adrenergic stimulation of oxygen consumption

1995 ◽  
Vol 269 (5) ◽  
pp. E960-E968 ◽  
Author(s):  
J. M. Ye ◽  
M. G. Clark ◽  
E. Q. Colquhoun
Keyword(s):  
Oxygen Consumption ◽  
Flow Rate ◽  
Constant Pressure ◽  
Constant Flow ◽  
Adrenergic Stimulation ◽  
Beta Adrenergic ◽  
Adrenergic Agents ◽  
Flow Perfusion ◽  
Stimulation Of

Isolated rat hindlimbs were perfused at 37 degrees C and constant physiological pressure (80 +/- 0.5 mmHg) while the flow rate that was allowed to freely self-adjust was monitored. Under these conditions, evidence was obtained for both alpha- and beta-adrenergic stimulation of oxygen consumption (VO2) in contrast to constant-flow perfusion, which has only convincingly shown alpha-adrenergic stimulation of VO2 in response to adrenergic agents. Addition of norepinephrine (NE; 1-33 nM) led to an increase in VO2 with a maximum of 29% above the basal value at 3.3 nM, even though the flow rate decreased. Phenylephrine (3.3-33 nM) and vasopressin (10-100 pM) also showed similar, but lesser in magnitude, vasoconstriction-associated stimulatory effects on VO2. Prazosin (an alpha 1-antagonist) completely reversed the NE-mediated decrease in flow rate and significantly blocked the increased VO2. In contrast, isoproterenol (10-1,000 nM) increased both flow rate (30%) and VO2 (32%). The isoproterenol-stimulated VO2 was not blocked by the beta 1-, beta 2-antagonist propranolol (10 microM), although the increased flow was reversed. In the presence of propranolol (1 or 10 microM), BRL-35135A (a beta 3-agonist) also stimulated VO2 (18%) without significant change in flow rate. These results lend further support to the role of the alpha 1-adrenoceptor in muscle VO2. In addition there is evidence for the presence of a functional beta 3-adrenoceptor as an additional subtype responsible for NE-mediated thermogenesis in the rat hindlimb.

Role of tissue hypermetabolism in stimulation of ventilation by dinitrophenol

1977 ◽  
Vol 43 (1) ◽  
pp. 72-74 ◽  
Author(s):  
S. Levine
Keyword(s):  
Oxygen Consumption ◽  
Metabolic Rate ◽  
Metabolic Changes ◽  
Arterial Infusion ◽  
Anesthetized Dogs ◽  
Small Increments ◽  
Large Increments ◽  
Stimulation Of

Several authors have hypothesized that tissue hypermetabolism accounts for increases in ventilation (VE) elicited by 2,4-dinitrophenol. However, some data in the literature indicate that stimulation of VE by isomers of dinitrophenol is unrelated to tissue metabolic rate. To test this latter concept, we compared three different isomers of dinitrophenol (i.e., 2,4-dinitrophenol (2,4-DNP), 2,5-dinitrophenol (2,5,-DNP), 2,6-dinitrophenol (2,6-DNP) with respect to stimulation of VE and with respect to stimulation of oxygen consumption (VO2). In all experiments, 3–4 mg/kg of one dinitrophenol isomer was administered to chloralose anesthetized dogs by intra-arterial infusion. 2,4-DNP elicited large increments in both VE and VO2, 2,6-DNP elicited moderate increments in both VE and VO2, whereas 2,5-DNP elicited small increments in both VE and VO2. These observations demonstrate a correlation between ventilatory and metabolic changes affected by isomers of dinitrophenol. Accordingly, these results are consistent with the hypothesis that ventilatory stimulation by congeners of dinitrophenol is related to tissue hypermetabolism.

Sign in / Sign up

Export Citation Format

Share Document