FACTORS AFFECTING THE INCORPORATION OF RADIOACTIVE PHOSPHATE INTO THE PHOSPHOLIPIDS OF SLICES OF CAT BRAIN

1954 ◽  
Vol 32 (1) ◽  
pp. 50-59 ◽  
Author(s):  
K. P. Strickland
Keyword(s):  
Oxygen Consumption ◽  
Inorganic Phosphate ◽  
Brain Slices ◽  
Phospholipid Fraction ◽  
Metabolic Inhibitors ◽  
Factors Affecting ◽  
Wide Range ◽  
Cat Brain

Slices of cat brain respiring in a Krebs–Ringer bicarbonate medium were found to incorporate radioactive inorganic phosphate (P32) into the phospholipid fraction. The addition of glucose or mannose increased the incorporation of P32 into the phospholipids. Fructose caused a small increase, whereas galactose was without effect. Pyruvate and lactate increased the incorporation of P32 into the phospholipids. Succinate, L (+)-glutamate, D (−)-glutamate, α keto-glutarate, citrate, and L-malate failed to support the incorporation.Anaerobic conditions and homogenization of the tissue prevented the in vitro incorporation of P32 into the phospholipids of cat brain. A wide range of metabolic inhibitors (cyanide, azide, malononitrile, chloretone, nembutal, iodoacetate, and fluoride), in concentrations that inhibit the oxygen consumption of brain slices, inhibited the incorporation. The incorporation was also inhibited by 2,4-dinitrophenol in concentrations that do not decrease the oxygen consumption of brain slices.These findings indicated that the incorporation of P32 into the phospholipids of slices of cat brain is a metabolic phenomenon and is dependent upon the maintenance of an adequate phosphorylating mechanism within the slice.

FACTORS AFFECTING THE INCORPORATION OF RADIOACTIVE PHOSPHATE INTO THE PHOSPHOLIPIDS OF SLICES OF CAT BRAIN

1954 ◽  
Vol 32 (1) ◽  
pp. 50-59 ◽  
Author(s):  
K. P. Strickland
Keyword(s):  
Oxygen Consumption ◽  
Inorganic Phosphate ◽  
Brain Slices ◽  
Phospholipid Fraction ◽  
Metabolic Inhibitors ◽  
Factors Affecting ◽  
Wide Range ◽  
Cat Brain

Slices of cat brain respiring in a Krebs–Ringer bicarbonate medium were found to incorporate radioactive inorganic phosphate (P32) into the phospholipid fraction. The addition of glucose or mannose increased the incorporation of P32 into the phospholipids. Fructose caused a small increase, whereas galactose was without effect. Pyruvate and lactate increased the incorporation of P32 into the phospholipids. Succinate, L (+)-glutamate, D (−)-glutamate, α keto-glutarate, citrate, and L-malate failed to support the incorporation.Anaerobic conditions and homogenization of the tissue prevented the in vitro incorporation of P32 into the phospholipids of cat brain. A wide range of metabolic inhibitors (cyanide, azide, malononitrile, chloretone, nembutal, iodoacetate, and fluoride), in concentrations that inhibit the oxygen consumption of brain slices, inhibited the incorporation. The incorporation was also inhibited by 2,4-dinitrophenol in concentrations that do not decrease the oxygen consumption of brain slices.These findings indicated that the incorporation of P32 into the phospholipids of slices of cat brain is a metabolic phenomenon and is dependent upon the maintenance of an adequate phosphorylating mechanism within the slice.

INCORPORATION OF RADIOACTIVE PHOSPHATE INTO NON-NUCLEOTIDE PROTEIN-BOUND PHOSPHORUS FRACTIONS OF RESPIRING CAT BRAIN SLICES

1954 ◽  
Vol 32 (1) ◽  
pp. 504-514
Author(s):  
Muriel Findlay ◽  
K. P. Strickland ◽  
R. J. Rossiter
Keyword(s):  
Inorganic Phosphate ◽  
Organic Phosphorus ◽  
Brain Slices ◽  
Phosphorus Fractions ◽  
Metabolic Inhibitors ◽  
Lipid Phosphorus ◽  
Wide Range ◽  
Cat Brain

Slices of cat brain respiring in a Krebs–Ringer bicarbonate medium were found to incorporate inorganic phosphate labelled with P32 into two non-nucleotide protein-bound phosphorus fractions, which are referred to as the residue organic phosphorus (ROP) and the "phosphoprotein" (PP), respectively. The addition of glucose or mannose to the medium increased the incorporation into both fractions. The addition of fructose, galactose, pyruvate, lactate, succinate, or L-glutamate failed to increase the incorporation into either fraction.Anaerobic conditions, homogenization of the tissue, or the addition of a wide range of metabolic inhibitors (cyanide, azide, iodoacetate, fluoride, nembutal, malononitrile, chloretone) inhibited the incorporation. The incorporation was also inhibited by 2,4-dinitrophenol in concentrations that do not inhibit oxygen consumption.These results are compared and contrasted with previous findings on the incorporation of P32 into the lipid phosphorus and pentosenucleic acid of brain slices.

INCORPORATION OF RADIOACTIVE PHOSPHATE INTO NON-NUCLEOTIDE PROTEIN-BOUND PHOSPHORUS FRACTIONS OF RESPIRING CAT BRAIN SLICES

1954 ◽  
Vol 32 (5) ◽  
pp. 504-514 ◽  
Author(s):  
Muriel Findlay ◽  
K. P. Strickland ◽  
R. J. Rossiter
Keyword(s):  
Inorganic Phosphate ◽  
Organic Phosphorus ◽  
Brain Slices ◽  
Phosphorus Fractions ◽  
Metabolic Inhibitors ◽  
Lipid Phosphorus ◽  
Wide Range ◽  
Cat Brain

Slices of cat brain respiring in a Krebs–Ringer bicarbonate medium were found to incorporate inorganic phosphate labelled with P32 into two non-nucleotide protein-bound phosphorus fractions, which are referred to as the residue organic phosphorus (ROP) and the "phosphoprotein" (PP), respectively. The addition of glucose or mannose to the medium increased the incorporation into both fractions. The addition of fructose, galactose, pyruvate, lactate, succinate, or L-glutamate failed to increase the incorporation into either fraction.Anaerobic conditions, homogenization of the tissue, or the addition of a wide range of metabolic inhibitors (cyanide, azide, iodoacetate, fluoride, nembutal, malononitrile, chloretone) inhibited the incorporation. The incorporation was also inhibited by 2,4-dinitrophenol in concentrations that do not inhibit oxygen consumption.These results are compared and contrasted with previous findings on the incorporation of P32 into the lipid phosphorus and pentosenucleic acid of brain slices.

EFFECTS OF X-RADIATION AND OF METABOLIC INHIBITORS ON RAT THYMOCYTES IN VITRO

1962 ◽  
Vol 40 (11) ◽  
pp. 1535-1552 ◽  
Author(s):  
D. K. Myers ◽  
Donna E. DeWolfe ◽  
Kimiko Araki
Keyword(s):  
Oxygen Consumption ◽  
Normal Cell ◽  
Cell Metabolism ◽  
Metabolic Inhibitors ◽  
Low Doses ◽  
Ph Values ◽  
Atp Levels ◽  
Different Temperatures ◽  
High Doses

The survival of X-irradiated thymocytes in vitro was studied after incubation for various periods of time and at different pH values as well as at different temperatures. Death at 25 °C following exposure to high doses of X-radiation may be due to the liberation of destructive enzymes. The effects of high doses could be largely prevented by addition of nicotinamide after irradiation.The cause of cell death at 37 °C following exposure to low doses of X-radiation is still uncertain. Some metabolic inhibitors also showed a considerable difference in their toxicity to thymocytes at 37 °C and at 25 °C. Dinitrophenol, for example, was highly toxic at 37 °C but almost ineffective in killing cells at 25 °C, even though it produced similar decreases in ATP levels at both temperatures. The marked difference in survival of irradiated thymocytes at 37 °C and at 25 °C could therefore be explained if low doses of X-radiation interfered with the normal cell metabolism. However, low doses of radiation, unlike dinitrophenol, did not produce any immediate decrease either in ATP levels or in oxygen consumption of thymocyte suspensions.

Orexin 2 Receptor (OX2R) Protein Distribution Measured by Autoradiography Using Radiolabeled OX2R-Selective Antagonist EMPA in Rodent Brain and Peripheral Tissues

2021 ◽  
Author(s):  
Kayo Mitsukawa ◽  
Haruhide Kimura
Keyword(s):  
Brain Slices ◽  
Brain Regions ◽  
Retrosplenial Cortex ◽  
Biological Functions ◽  
Protein Distribution ◽  
Peripheral Tissues ◽  
Physiological Functions ◽  
Wide Range ◽  
The Central Nervous System

Abstract Orexin, a neuropeptide, performs various physiological functions, including the regulation of emotion, feeding, metabolism, respiration, and sleep/wakefulness, by activating the orexin 1 receptor and orexin 2 receptor (OX2R). Owing to the pivotal role of OX2R in wakefulness and other biological functions, OX2R agonists are being developed. A detailed understanding of OX2R protein distribution is essential for determining the mechanisms of action of OX2R agonists; however, this has been hindered by the lack of selective antibodies. In this study, we first confirmed the OX2R-selective binding of [3H]-EMPA in in vitro autoradiography studies, using brain slices from OX2R knockout mice and their wild-type littermates. Subsequently, OX2R protein distribution in rats was comprehensively assessed in 51 brain regions and 10 peripheral tissues using in vitro autoradiography with [3H]-EMPA. The widespread distribution of OX2R protein, including that in previously unrecognized regions of the retrosplenial cortex and suprachiasmatic nucleus of the hypothalamus, was identified. In contrast, negligible/very low OX2R protein expression was observed in peripheral tissues, suggesting that orexin exerts OX2R-dependent physiological functions primarily through activation of the central nervous system. These data would be useful for understanding the wide range of biological functions of OX2R and the application of OX2R agonists in various disorders.

Variability in the chemical composition of cereal straws and in vitro digestibility with and without sodium hydroxide treatment

1979 ◽  
Vol 19 (98) ◽  
pp. 350 ◽  
Author(s):  
GR Pearce ◽  
J Beard ◽  
EP Hilliard
Keyword(s):  
In Vitro Digestibility ◽  
Sodium Potassium ◽  
Factors Affecting ◽  
Wide Range ◽  
Acid Detergent Fibre ◽  
Gross Energy ◽  
Calcium Magnesium ◽  
Straw Quality ◽  
Sodium Hydroxide Treatment

A total of 28 samples of wheat, oat and barley straws showed a wide range in concentration of nitrogen, ash, gross energy, neutral detergent fibre, acid detergent fibre, lignin, cellulose, hemicellulose, residual ash, calcium, magnesium, sodium, potassium and phosphorus. Four straws that had suffered rain damage before collection ranged in in vitro organic matter digestibility from 25 to 34%, compared with 30 to 49% for the other straws; after treatment with 6 g NaOH per 100 g dry matter the ranges were 42 to 46% and 43 to 62%, respectively. The need to determine the effects of the various factors affecting straw quality is emphasized.

scholarly journals A fluorescent sensor for spatiotemporally resolved endocannabinoid dynamics in vitro and in vivo

2020 ◽  
Author(s):  
Ao Dong ◽  
Kaikai He ◽  
Barna Dudok ◽  
Jordan S Farrell ◽  
Wuqiang Guan ◽  
...  
Keyword(s):  
Membrane Trafficking ◽  
Basolateral Amygdala ◽  
Fluorescent Sensor ◽  
Brain Slices ◽  
High Specificity ◽  
Cultured Neurons ◽  
Spatiotemporal Resolution ◽  
Wide Range

Endocannabinoids (eCBs) are retrograde neuromodulators that play an important role in a wide range of physiological processes; however, the release and in vivo dynamics of eCBs remain largely unknown, due in part to a lack of suitable probes capable of detecting eCBs with sufficient spatiotemporal resolution. Here, we developed a new eCB sensor called GRABeCB2.0. This genetically encoded sensor consists of the human CB1 cannabinoid receptor fused to circular-permutated EGFP, providing cell membrane trafficking, second-resolution kinetics, high specificity for eCBs, and a robust fluorescence response at physiological eCB concentrations. Using the GRABeCB2.0 sensor, we monitored evoked changes in eCB dynamics in both cultured neurons and acute brain slices. Interestingly, in cultured neurons we also observed spontaneous compartmental eCB transients that spanned a distance of approximately 11 μm, suggesting constrained, localized eCB signaling. Moreover, by expressing GRABeCB2.0 in the mouse brain, we readily observed foot shock-elicited and running-triggered eCB transients in the basolateral amygdala and hippocampus, respectively. Lastly, we used GRABeCB2.0 in a mouse seizure model and observed a spreading wave of eCB release that followed a Ca2+ wave through the hippocampus. Thus, GRABeCB2.0 is a robust new probe for measuring the dynamics of eCB release under both physiological and pathological conditions.

EFFECTS OF LONG-TERM TREATMENT AND OF LOW CONCENTRATIONS OF THYROID HORMONES ON THE OXYGEN UPTAKE OF TOAD TISSUES

1966 ◽  
Vol 36 (3) ◽  
pp. 221-229 ◽  
Author(s):  
C. C. THORNBURN ◽  
A. J. MATTY
Keyword(s):  
Oxygen Consumption ◽  
Oxygen Uptake ◽  
Bufo Bufo ◽  
Term Treatment ◽  
Seasonal Effect ◽  
Long Term Treatment ◽  
Wide Range ◽  
Two Peaks

SUMMARY Isolated tissues of the toad Bufo bufo (urinary bladder, skin and kidney) were treated in vitro with thyroxine (T4) or tri-iodothyronine (T3) both with and without prior administration of the hormones in vivo. They were incubated at low temperature, and their oxygen consumption studied for 48 hr. Both hormones had little effect in vitro. Pretreatment with T4 in vivo usually lowered oxygen uptake; the effect of pretreatment with T3 varied. The presence of alanine in the incubating medium caused a marked increase in oxygen consumption. A seasonal effect was also found. The respiration of isolated toad bladder was stimulated by a wide range of concentrations of thyroxine in vitro, and there were two peaks of stimulation.

EFFECTS OF X-RADIATION AND OF METABOLIC INHIBITORS ON RAT THYMOCYTES IN VITRO

1962 ◽  
Vol 40 (1) ◽  
pp. 1535-1552 ◽  
Author(s):  
D. K. Myers ◽  
Donna E. DeWolfe ◽  
Kimiko Araki
Keyword(s):  
Oxygen Consumption ◽  
Normal Cell ◽  
Cell Metabolism ◽  
Metabolic Inhibitors ◽  
Low Doses ◽  
Ph Values ◽  
Atp Levels ◽  
Different Temperatures ◽  
High Doses

The survival of X-irradiated thymocytes in vitro was studied after incubation for various periods of time and at different pH values as well as at different temperatures. Death at 25 °C following exposure to high doses of X-radiation may be due to the liberation of destructive enzymes. The effects of high doses could be largely prevented by addition of nicotinamide after irradiation.The cause of cell death at 37 °C following exposure to low doses of X-radiation is still uncertain. Some metabolic inhibitors also showed a considerable difference in their toxicity to thymocytes at 37 °C and at 25 °C. Dinitrophenol, for example, was highly toxic at 37 °C but almost ineffective in killing cells at 25 °C, even though it produced similar decreases in ATP levels at both temperatures. The marked difference in survival of irradiated thymocytes at 37 °C and at 25 °C could therefore be explained if low doses of X-radiation interfered with the normal cell metabolism. However, low doses of radiation, unlike dinitrophenol, did not produce any immediate decrease either in ATP levels or in oxygen consumption of thymocyte suspensions.

Drug uptake into everted intestinal sacs. II. Inhibition of secretion by hypertonicity.

1979 ◽  
Vol 236 (1) ◽  
pp. E57
Author(s):  
A Hurwitz
Keyword(s):  
Oxygen Consumption ◽  
Oxygen Uptake ◽  
Glucose Uptake ◽  
Drug Uptake ◽  
Metabolic Inhibitors ◽  
Rat Jejunum ◽  
Intestinal Tissue ◽  
Active Secretion ◽  
Influx Rate

Mucosal hypertonicity, metabolic inhibitors, or absence of glucose and oxygen enhance mucosal-to-serosal influx of the cationic drug, pralidoxime (PAM), into sacs of everted rat jejunum in vitro. Conversely, efflux of PAM, which is twice the influx rate, is inhibited by mucosal hypertonicity or cyanide and iodoacetate. When sacs containing PAM, 0.87 mM, and glucose, 10 mM, were placed in identical drug- and sugar-containing mediums, the inside (serosal) concentration of PAM fell by over half in 120 min, whereas that of glucose more than doubled. Mucosal hypertonicity depressed PAM efflux and glucose influx regardless of serosal osmolarity. Although azide and mucosal hypertonicity each depressed glucose uptake and oxygen consumption while accelerating net PAM influx, azide more effectively depressed glucose and oxygen uptake, whereas hypertonicity caused greater acceleration of PAM uptake. Hypertonicity did not affect PAM binding to intestinal tissue. Varying mucosal pH did not change PAM or glucose uptake. Thus, mucosal hypertonicity apparently enhances net mucosal-to-serosal transfer of PAM by blocking its active secretion from serosa to mucosa.

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