scholarly journals Lactate utilization by the neonatal rat brain in vitro. Competition with glucose and 3-hydroxybutyrate

1986 ◽  
Vol 234 (2) ◽  
pp. 489-492 ◽  
Author(s):  
E Fernández ◽  
J M Medina
Keyword(s):  
Rat Brain ◽  
Glucose Utilization ◽  
Brain Slices ◽  
Neonatal Rat ◽  
Neonatal Brain ◽  
Lactate Oxidation ◽  
Inhibited Oxidation ◽  
Lactate Utilization ◽  
Neonatal Rat Brain

The maximum rates of lactate oxidation and lipogenesis from lactate by early-neonatal brain slices were considerably greater than those for utilization of glucose and 3-hydroxybutyrate at physiological concentrations. Lactate inhibited glucose utilization, but enhanced 3-hydroxybutyrate utilization. 3-Hydroxybutyrate inhibited lactate and glucose utilization. Glucose slightly inhibited oxidation of lactate and 3-hydroxybutyrate, but scarcely enhanced lipogenesis from these substrates.

Acute hypoxia induces elevation of ornithine decarboxylase activity in neonatal rat brain slices

1995 ◽  
Vol 7 (3) ◽  
pp. 385 ◽  
Author(s):  
LD Longo ◽  
S Packianathan
Keyword(s):  
Rat Brain ◽  
Ornithine Decarboxylase ◽  
Bovine Serum ◽  
Brain Slice ◽  
Brain Slices ◽  
Neonatal Rat ◽  
Newborn Rat ◽  
Rat Brain Slice

Recent studies in vivo have demonstrated that ornithine decarboxylase (ODC) activity in the fetal rat brain is elevated 4-5-fold by acute maternal hypoxia. This hypoxic-associated increase is seen in the rat brain in both the newborn and the adult. Because of the intimate involvement of ODC in transcription and translation, as well as in growth and development, it is imperative that the manner in which hypoxia affects the regulation of this enzyme be better understood. In order to achieve this, a brain preparation in vitro was required to eliminate the confounding effects of the dam on the fetal and newborn brain ODC activity in vivo. Therefore, brain slices from 3-4-day-old (P-3) newborn rats were utilized to test the hypothesis that ODC activity increases in response to hypoxia in vitro. Cerebral slices from the P-3 rat pups were allowed to equilibrate and recover in artificial cerebrospinal fluid (ACSF) continuously bubbled with a mixture of 95% O2 and 5% CO2 for 1 h before beginning hypoxic exposures. Higher basal ODC activities were obtained by treating the slices with 0.03% fetal bovine serum (FBS) and 0.003% bovine serum albumin (BSA), rather than with ACSF alone. Hypoxia was induced in the slices by replacing the gas with 40%, 21%, 10%, or 5% O2, all with 5% CO2 and balance N2. With FBS and BSA treatment, ODC activity was maintained at about 0.15-0.11 nM CO2 mg-1 protein h-1 throughout the experiment, which was 2-3-fold higher than that without FBS and BSA. ODC activity increased significantly and peaked between 1 h and 2 h after initiation of hypoxia. For instance, with 21% O2, ODC activity increased approximately 1.5-fold at 1 h and approximately 2-fold at 2 h. These studies demonstrate that: (1) the hypoxic-induced increases observed in vivo in the fetal and newborn rat brain ODC activity can be approximated in a newborn rat brain slice preparation in vitro; (2) newborn rat brain slice preparations may provide an alternative to methods in vivo or cell culture methods for studying the regulation of acute hypoxic-induced enzymes; and (3) high, stable baseline ODC activities in brain slices suggest that the cells in the slice are capable of active metabolism if FBS and BSA are available to mimic conditions in vivo.

19F NMR calcium changes, edema and histology in neonatal rat brain slices during glutamate toxicity

1994 ◽  
Vol 647 (1) ◽  
pp. 172-176 ◽  
Author(s):  
Maryceline T. Espanol ◽  
Lawrence Litt ◽  
Yan Xu ◽  
Lee-Hong Chang ◽  
Thomas L. James ◽  
...  
Keyword(s):  
Rat Brain ◽  
Brain Slices ◽  
Neonatal Rat ◽  
19F Nmr ◽  
Glutamate Toxicity ◽  
Neonatal Rat Brain

scholarly journals Hypercarbia and Mild Hypothermia, Only When Not Combined, Improve Postischemic Bioenergetic Recovery in Neonatal Rat Brain Slices

2000 ◽  
Vol 20 (3) ◽  
pp. 612-619 ◽  
Author(s):  
Robert C. Tasker ◽  
Sati K. Sahota ◽  
Stephen R. Williams
Keyword(s):  
Mild Hypothermia ◽  
Ex Vivo ◽  
Brain Slices ◽  
Neonatal Rat ◽  
Resonance Spectroscopy ◽  
Immature Brain ◽  
Bicarbonate Buffer ◽  
Cellular Energy ◽  
Neonatal Rat Brain

In the immature brain, postischemic metabolism may be influenced beneficially by the effect of inducing hypercarbia or hypothermia. With use of 31P nuclear magnetic resonance spectroscopy, intracellular pH (pHi) and cellular energy metabolites in ex vivo neonatal rat cerebral cortex were measured before, during, and after substrate and oxygen deprivation in in vitro ischemia. Early postischemic hypothermia (fall in temperature −3.2 ± 1.0°C) delayed the normalization of pHi after ischemia by inducing an acid shift in pHi ( P < 0.01). Postischemic hypercarbia (Krebs—Henseleit bicarbonate buffer equilibrated with 10% carbon dioxide in oxygen) and hypothermia induced separate, but potentially additive, reversible decreases in pHi, each of approximately −0.16 pH unit ( P < 0.05). When these postischemic perturbations were applied in isolation, there was significant improvement of ∼20% in the recovery of β-ATP ( P < 0.05). In combination, however, hypercarbia and hypothermia worsened recovery in ATP by ∼20% ( P < 0.05). In control tissue, which had not been exposed to ischemia, ATP content was also significantly reduced by co-administration of the two treatments ( P < 0.05), an effect that persisted even after discontinuing the perturbing conditions. Therefore, in this vascular-independent neonatal preparation, early postischemic modulation of metabolism by hypercarbia or hypothermia appears to confer improved bioenergetic recovery, but only if they are not administered together.

Acetylation of cortisol by neonatal rat brain in vitro

Steroids ◽  
1967 ◽  
Vol 9 (2) ◽  
pp. 229-234 ◽  
Author(s):  
B.I. Grosser ◽  
L.R. Axelrod
Keyword(s):  
Rat Brain ◽  
Neonatal Rat ◽  
Neonatal Rat Brain

PI3K inhibition in neonatal rat brain slices during and after hypoxia reduces phospho-Akt and increases cytosolic cytochrome c and apoptosis

2004 ◽  
Vol 124 (1) ◽  
pp. 51-61 ◽  
Author(s):  
Kiyoshi Hirai ◽  
Takeshi Hayashi ◽  
Pak H. Chan ◽  
Jianying Zeng ◽  
Guo-Yuan Yang ◽  
...  
Keyword(s):  
Cytochrome C ◽  
Rat Brain ◽  
Brain Slices ◽  
Neonatal Rat ◽  
Pi3k Inhibition ◽  
Neonatal Rat Brain ◽  
Cytosolic Cytochrome
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