Synthesis of, and Animal Experiments with, N-Isopropyl-p-123I-Iodo-Amphetamine (IMP) and 18F-3-Deoxy-3Fluoro-D-Glucose (3-FDG) as Tracers in Brain and Heart Diagnostic Studies

1984 ◽  
Vol 22 (01) ◽  
pp. 31-34 ◽  
Author(s):  
E. J. Knust ◽  
R. M. Baldwin ◽  
T. Chen ◽  
L. E. Feinendegen ◽  
H.-J. Machulla
Keyword(s):  
Clinical Studies ◽  
Half Life ◽  
Time Course ◽  
Animal Experiments ◽  
Concomitant Increase ◽  
Brain Functions ◽  
A Value ◽  
The Brain

SummaryGermanyFor the investigation of brain functions 18F-3-deoxy-3-fluoro-D-glucose (3-FDG) and N-isopropyl-p-123I-iodoamphetamine (IMP) were synthesized and the course of radioactivity measured in several organs of mice. The results can be summarized as follows:1.IMP is rapidly extracted from the blood and reaches a value of less than 1%/g within the first 15 min;2.123I-radioactivity in the lungs shows a maximum of 76%/g as soon as half a minute after injection and decreases with a concomitant increase in the liver and brain;3. The maximum 123I-uptake in the brain of 11%/g is reached after 30 min and levels off at a constant value of 10%/g;4. 30 min after injection the brain/ blood ratio for IMP is about 14;5. The time course of 3-FDG in the brain has a maximum of 4.8%/g as soon as 5 min after injection and decreases to a constant value of 3%/g within 1 hr; and6. Accumulation of 18F-radioactivity in the heart reaches a maximum of 14%/g after 1 hr and is eliminated with a half-life of 300 min. Comparative clinical studies with 3-FDG and 3-0-11C-methyl-D-glucose (ÇMG) have shown that 3-FDG can be considered as a CMG-analogue and thus can be used for the in-vivo determination of local glucose perfusion and transport rates.

Determination of rat brain buffering in vivo by 31P-NMR

1988 ◽  
Vol 64 (5) ◽  
pp. 1829-1836 ◽  
Author(s):  
S. Adler ◽  
V. Simplaceanu ◽  
C. Ho
Keyword(s):  
Rat Brain ◽  
Time Course ◽  
Sprague Dawley ◽  
Sprague Dawley Rats ◽  
Brain Ph ◽  
Acid Extrusion ◽  
The Brain ◽  
Full Activation

Buffering capacity of most tissues is composed of both rapid and slow phases, the latter presumably due to active acid extrusion. To examine the time course of brain buffering the brain pH of Sprague-Dawley rats was measured using 31P-nuclear magnetic resonance. The effect on brain pH of 30- or 58-min exposures to 20% CO2 followed by 30- or 38-min recovery periods, respectively, was studied. Brain pH reached its lowest value after a 15-min exposure to elevated CO2, thereafter slowly and steadily increasing. During recovery brain pH rose rapidly in the first 5 min exceeding control brain pH by 0.08 pH units. Brain pH fell during the next 30 min despite increases in blood pH and decreases in blood CO2 tension. Calculated intrinsic brain buffering rose steadily threefold during the last 40 min of CO2 exposure and during the final 30 min of recovery. These data show that in rat brain there is a temporally late buffering process, most likely active acid extrusion, requiring greater than 30 min for full activation and at least 30 min for discontinuation.

scholarly journals Emergence Of Consciousness And Qualia From A Complex Brain

Folia Medica ◽  
2014 ◽  
Vol 56 (4) ◽  
pp. 289-296
Author(s):  
Jakob Korf
Keyword(s):  
System Theory ◽  
General System ◽  
Resolution Power ◽  
Brain Functions ◽  
Scientific Exploration ◽  
Brain Changes ◽  
Higher Brain Functions ◽  
The Brain

Abstract Qualia are private conscious experiences of which the associated feelings can be reported to other people. Whether qualia are amenable to scientific exploration has often been questioned, which is challenged by the present article. The following arguments are given: 1. the configuration of the brain changes continuously and irreversibly, because of genetic and environmental influences and interhuman communication; 2. qualia and consciousness are processes, rather than states; 3. private feelings, including those associated with qualia, should be positioned in the context of a personal brain as being developed during life; 4. consciousness and qualia should be understood in the context of general system theory, thus concluding that isolated, in vitro, properties of neurons and other brain constituents might marginally contribute to the understanding of higher brain functions, mind or qualia; 5. current in vivo approaches have too little resolution power - in terms of space and time - to delineate individual and subjective brain processes. When subtle personalized properties of the nervous system can be assessed in vivo or in vitro, qualia can scientifically be investigated. We discuss some approaches to overcome these barriers.

Effects of hypercapnia on ECoG and oxidative metabolism in neonatal dog brain

1995 ◽  
Vol 78 (6) ◽  
pp. 2272-2278 ◽  
Author(s):  
H. Yoshioka ◽  
H. Miyake ◽  
D. S. Smith ◽  
B. Chance ◽  
T. Sawada ◽  
...  
Keyword(s):  
Electrical Activity ◽  
Resonance Spectroscopy ◽  
Respiratory Enzymes ◽  
Arterial Pco2 ◽  
A Value ◽  
Electrocorticogram Ecog ◽  
The Brain ◽  
Mitochondrial Respiratory

The effects of hypercapnia on cerebral electrical activity and mitochondrial oxidative phosphorylation were studied in the anesthetized neonatal dog by using the electrocorticogram (ECoG) and 31P-magnetic resonance spectroscopy. Three levels of hypercapnia with arterial PCO2 values of approximately 70, 100, and 140 Torr reduced the intracellular pH of the brain from 7.11 to 6.99, 6.87, and 6.76, respectively. These levels of hypercapnia also reduced ADP concentration ([ADP]) from 21.5 to 18.1, 14.8, and 12.9 microM as well as the average ECoG power output by 20, 30, and 40%. A Michaelis-Menten relationship for the mitochondrial respiratory enzymes was fitted with [ADP] and the change in the average ECoG. The result suggests that mitochondrial respiration is regulated by [ADP] and that the in vivo Michaelis-Menten constant for ADP was 21 microM, a value close to the in vitro value. The mitochondrial maximal reaction velocity was reduced by only 10% during hypercapnia and showed no relationship with the degree of acidosis, suggesting that mitochondrial respiratory enzymes are not responsible for the inhibition of the brain electrical activity.

scholarly journals A study on Dowager Cixi’s Yanling-Yishou-Dan of Qing Dynasty in a Japanese laboratory of biochemistry and molecular biology in 1990s: An attempt for TCM modernization

2021 ◽  
pp. 1-21
Author(s):  
Jiankang Liu
Keyword(s):  
Qing Dynasty ◽  
Brain Homogenate ◽  
Modern Technology ◽  
Toxicity Tests ◽  
Brain Functions ◽  
Great Progress ◽  
Theoretical Evidence ◽  
The Brain

Traditional Chinese Medicine (TCM) modernization has been proposed for many years, but the progress is still slow due to both ideological and technical obstacles. When I went to Japan in 1989, I found Japan has made a great progress on TCM by using modern technology. Therefore, I have studied a fine extract prepared from medicinal herbs (renamed Yi-Zhi-Yi-Shou, YZYS), a prescription of Dowager Cixi’s Yanling-Yishou-Dan of Qing Dynasty, with the current drug investigation strategies. I examined its antioxidant activity both in vitro and in vivo. The in-vitro studies found that YZYS possesses strong antioxidant capacity, such as scavenging various kinds of free radicals, and inhibits free radical-induced peroxidation of brain homogenate, microsomes, mitochondria, amino acids, deoxyribose and DNA. The in-vivo study with immobilization-induced emotional stress in rats, showed that YZYS effectively inhibits stress-induced stomach ulcers and oxidative damage in plasma and the brain. In addition, YZYS is shown to be non-toxic in both acute and chronic toxicity tests. These studies demonstrate that YZYS is a potent natural antioxidant and offer theoretical evidence for the beneficial effect of YZYS on health and brain functions, and that TCM prescriptions can be studied scientifically as modern medical drugs.

Metabolomic Alterations in the Blood and Brain in Association with Alzheimer’s Disease: Evidence from in vivo to Clinical Studies

2021 ◽  
pp. 1-28
Author(s):  
Sirawit Sriwichaiin ◽  
Nipon Chattipakorn ◽  
Siriporn C. Chattipakorn
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Clinical Studies ◽  
Elderly Population ◽  
The Elderly ◽  
Pathological Findings ◽  
Major Health Problem ◽  
Major Health ◽  
The Brain

Alzheimer’s disease (AD) has become a major health problem among the elderly population. Some evidence suggests that metabolic disturbance possibly plays a role in the pathophysiology of AD. Currently, the study of metabolomics has been used to explore changes in multiple metabolites in several diseases, including AD. Thus, the metabolomics research in AD might provide some information regarding metabolic dysregulations, and their possible associated pathophysiology. This review summarizes the information discovered regarding the metabolites in the brain and the blood from the metabolomics research of AD from both animal and clinical studies. Additionally, the correlation between the changes in metabolites and outcomes, such as pathological findings in the brain and cognitive impairment are discussed. We also deliberate on the findings of cohort studies, demonstrating the alterations in metabolites before changes of cognitive function. All of these findings can be used to inform the potential identity of specific metabolites as possible biomarkers for AD.

Sensitive enzyme electrodes

1990 ◽  
Vol 333 (1628) ◽  
pp. 49-61 ◽  
Keyword(s):  
Packed Bed ◽  
Current Time ◽  
Enzyme Electrodes ◽  
Freely Moving ◽  
The Brain ◽  
Nanomolar Range ◽  
Inhibited Enzyme ◽  
Micromolar Range

Conventional enzyme electrodes are relatively insensitive devices capable of measuring analytes in the micromolar range. Inhibited enzyme electrodes work by measuring the inhibition of an enzyme turning over undersaturated conditions. This increased turnover gives greater sensitivity. The detection limits are controlled either by the thermodynamic amplitude or by the kinetic discrimination. Software has been developed to analyse the current time transient to produce concentrations of the inhibitor. Results for CN- and H 2 S are presented. The packed bed wall jet electrode is an electrode assembly that allows complete reaction of the substrate with the enzyme coupled to an efficient hydrodynamic régime for electrochemical detection. Results for the determination of acetylcholine are presented. The electrode can also be used in an immunoassay for the determination of human immunoglobulin in the nanomolar range. Finally results will be presented for in vivo changes in ascorbate in the brain of the freely moving rat as a result of tail pinch; changes on a timescale of half a second can be followed.

In-vivo evaluation of dopamine receptor-mediated inhibition of gonadotrophin secretion from the pituitary gland of the goldfish, Carassius auratus

1987 ◽  
Vol 114 (3) ◽  
pp. 449-458 ◽  
Author(s):  
R. J. Omeljaniuk ◽  
S. H. Shih ◽  
R. E. Peter
Keyword(s):  
Dopamine Receptor ◽  
Carassius Auratus ◽  
Time Course ◽  
Dopamine Antagonists ◽  
Serum Concentrations ◽  
In Vivo Evaluation ◽  
Goldfish Carassius Auratus ◽  
Dopamine Receptor Antagonists ◽  
The Brain

ABSTRACT Dopamine acts directly on the pituitary to modulate gonadotrophin (GtH) secretion in goldfish (Carassius auratus). In the light of this important role for dopamine in the regulation of goldfish reproduction, this investigation was designed to evaluate the receptor specificity of this dopamine inhibition and to describe the use of domperidone, a specific dopamine D2-receptor antagonist, in the manipulation of pituitary function in goldfish. To investigate the specificity of dopamine inhibition of GtH secretion, selected dopamine receptor antagonists were injected i.p. to block dopamine receptors thereby increasing GtH secretion as reflected by increased serum concentrations of GtH. Serum GtH levels were significantly increased by the active stereoisomer (−)-sulpiride in a dose-related fashion; (+)-sulpiride had no effect. Comparison of dopamine antagonists at low doses indicated that only domperidone and pimozide caused significant increases in serum concentrations of GtH. Dopamine antagonists potentiated the action of a gonadotrophin-releasing hormone analogue (GnRH-A) with an order of potency of domperidone = pimozide > metoclopramide = fluphenazine. [3H]Domperidone, injected i.p. with unlabelled domperidone, entered the blood and achieved maximum concentrations 12 h after injection, but did not accumulate in the brain in appreciable amounts. Gonadal 3H radioactivity was usually equal to or in excess of blood radioactivity, while [3H]domperidone was highly concentrated in the pituitary in a time-dependent fashion, with maximal accumulation occurring 24 h after injection. The time-course of pituitary accumulation of [3H]domperidone correlated well with the temporal increase in serum GtH levels in response to i.p. injected domperidone or domperidone plus an analogue of LHRH. Domperidone increased serum concentrations of GtH in a dose-related fashion; an analogue of salmon GnRH (sGnRH-A) increased the sensitivity and magnitude of the serum GtH response to domperidone. Serum concentrations of GtH were increased by sGnRH-A in a dose-related fashion; a low dose of domperidone substantially increased the sensitivity of the serum GtH response to sGnRH-A. These results indicate that dopamine inhibits GtH secretion from the goldfish pituitary by acting through a specific mechanism mediated by a dopamine D2 receptor. Domperidone increased serum concentrations of GtH, potentiated the action of gonadotrophin-releasing hormones and did not pass into the brain after i.p. injection into goldfish. The data also suggest that dopamine and GnRH, although acting through different receptors, influence the effect of each other on GtH release. J. Endocr. (1987) 114, 449–458

Sign in / Sign up

Export Citation Format

Share Document