The importance of skeletal muscles as a distribution volume for digitalis glycosides in guinea-pigs and human subjects

1986 ◽  
pp. 245-255 ◽  
Author(s):  
Keld Kjeldsen
Keyword(s):  
Guinea Pigs ◽  
Skeletal Muscles ◽  
Human Subjects ◽  
Distribution Volume ◽  
Digitalis Glycosides

scholarly journals The fate of cyclamate in man and other species

1972 ◽  
Vol 129 (4) ◽  
pp. 869-879 ◽  
Author(s):  
A. G. Renwick ◽  
R. T. Williams
Keyword(s):  
Single Dose ◽  
Gastrointestinal Tract ◽  
Biliary Excretion ◽  
Guinea Pigs ◽  
Human Subjects ◽  
Gut Flora

1. 14C-labelled cyclamate has been administered to guinea pigs, rabbits, rats and humans. When given orally to these species on a cyclamate-free diet, cyclamate is excreted unchanged. In guinea pigs some 65% of a single dose is excreted in the urine and 30% in the faeces, the corresponding values for rats being 40 and 50%, for man, 30–50% and 40–60%, and for rabbits, 90 and 5%, the excretion being over a period of 2–3 days. 2. Cyclamate appears to be readily absorbed by rabbits but less readily by guinea pigs, rats and humans. 3. If these animals, including man, are placed on a diet containing cyclamate they develop the ability to convert orally administered cyclamate into cyclohexylamine and consequently into the metabolites of the latter. The extent to which this ability develops is variable, the development occurring more readily in rats than in rabbits or guinea pigs. In three human subjects, one developed the ability quite markedly in 10 days whereas two others did not in 30 days. Removal of the cyclamate from the diet caused a diminution in the ability to convert cyclamate into the amine. 4. In rats that had developed the ability to metabolize orally administered cyclamate, intraperitoneally injected cyclamate was not metabolized and was excreted unchanged in the urine. The biliary excretion of injected cyclamate in rats was very small, i.e. about 0.3% of the dose. 5. The ability of animals to convert cyclamate into cyclohexylamine appears to depend upon a continuous intake of cyclamate and on some factor in the gastrointestinal tract, probably the gut flora.

scholarly journals Autonomic nerve receptors in the allergic nasal mucosa in the human subjects and the sensitized guinea pigs.

1985 ◽  
Vol 88 (9) ◽  
pp. 1153-1161
Author(s):  
NOBUHISA TERADA ◽  
AKIYOSHI KONNO ◽  
YOSHITAKA OKAMOTO
Keyword(s):  
Nasal Mucosa ◽  
Guinea Pigs ◽  
Human Subjects ◽  
Autonomic Nerve

GROWTH

PEDIATRICS ◽  
1950 ◽  
Vol 5 (5) ◽  
pp. 765-770
Author(s):  
ALFRED H. WASHBURN
Keyword(s):  
San Francisco ◽  
Guinea Pigs ◽  
Research Council ◽  
Human Subjects ◽  
Healthy Development ◽  
The Past ◽  
Child Research ◽  
The Family ◽  
New Knowledge ◽  
To Receive

IT IS with a very real sense of humility that I accept the Borden Award from the Academy of Pediatrics. I am happy to receive it in San Francisco since this was the scene of some of my earlier adventures in pediatrics. It is not quite polite, I suppose, to question the wisdom of the committee which made this award. Perhaps, however, its members will not be offended if I point out that I am only one member of a team—that such contributions as have been made from the Child Research Council during the past two decades are the product of the teamwork and loyalty of many investigators. A brief description of our institute will serve as an easy introduction to my subject. We are following intensively a small group of individuals. At present we have 137, ranging in age from birth to 25 years. Each new baby is registered in the study early in his prenatal career. Thus we have the opportunity of knowing something about the mother's health and diet, as well as some beginning understanding of the family and home into which this new human being is to be born. Each baby is then observed frequently, regularly, and from many different aspects through infancy, childhood, adolescence and on into the mature years; for we have become an institute engaged in following the whole life-span of individual persons. We try to make use of the wisdom and skills from many fields of science. We are not using human subjects as "guinea pigs" to contribute new knowledge to a specific field but, instead, all fields of science are being utilized to contribute to an awareness of the unique individuality of each child—to an understanding of how his own peculiar characteristics and patterns of growth contribute to his chance for healthy development and happy adaptation to his environment.

The Apparent Digestibility of Essentially Similar Diets by Rats, Guinea Pigs, Sheep, Swine and by Human Subjects

1951 ◽  
Vol 43 (4) ◽  
pp. 541-550 ◽  
Author(s):  
Earle W. Crampton ◽  
M. Isabel Irwin ◽  
Lewis E. Lloyd ◽  
Helen R. Neilson
Keyword(s):  
Guinea Pigs ◽  
Human Subjects ◽  
Apparent Digestibility

scholarly journals N-acetyltaurine and Acetylcarnitine Production for the Mitochondrial Acetyl-CoA Regulation in Skeletal Muscles during Endurance Exercises

Metabolites ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 522
Author(s):  
Teruo Miyazaki ◽  
Yuho Nakamura-Shinya ◽  
Kei Ebina ◽  
Shoichi Komine ◽  
Song-Gyu Ra ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Palmitic Acid ◽  
Skeletal Muscles ◽  
Metabolic Flux ◽  
Human Subjects ◽  
Tca Cycle ◽  
Blood Levels ◽  
Acetyl Coa ◽  
The Tca Cycle ◽  
Human Skeletal Muscle Cells

During endurance exercises, a large amount of mitochondrial acetyl-CoA is produced in skeletal muscles from lipids, and the excess acetyl-CoA suppresses the metabolic flux from glycolysis to the TCA cycle. This study evaluated the hypothesis that taurine and carnitine act as a buffer of the acetyl moiety of mitochondrial acetyl-CoA derived from the short- and long-chain fatty acids of skeletal muscles during endurance exercises. In human subjects, the serum concentrations of acetylated forms of taurine (NAT) and carnitine (ACT), which are the metabolites of acetyl-CoA buffering, significantly increased after a full marathon. In the culture medium of primary human skeletal muscle cells, NAT and ACT concentrations significantly increased when they were cultured with taurine and acetate or with carnitine and palmitic acid, respectively. The increase in the mitochondrial acetyl-CoA/free CoA ratio induced by acetate and palmitic acid was suppressed by taurine and carnitine, respectively. Elevations of NAT and ACT in the blood of humans during endurance exercises might serve the buffering of the acetyl-moiety in mitochondria by taurine and carnitine, respectively. The results suggest that blood levels of NAT and ACT indicate energy production status from fatty acids in the skeletal muscles of humans undergoing endurance exercise.

scholarly journals An animal model to study iron availability from human diets

1977 ◽  
Vol 37 (3) ◽  
pp. 451-456 ◽  
Author(s):  
B. S. Narasinga Rao ◽  
J. Siva Prasad ◽  
C. Vijaya Sarathy
Keyword(s):  
Animal Model ◽  
Guinea Pigs ◽  
Ferrous Iron ◽  
Human Subjects ◽  
Whole Body ◽  
Iron Availability ◽  
Retention Ratio ◽  
Ferrous Ascorbate ◽  
Body Counting ◽  
Whole Body Counting

1. The retention of ferric- and ferrous-iron was determined in guinea-pigs and monkeys using55Fe and59Fe.2. The bioavailability of Fe from two typical Indian diets based on rice and wheat was determined in humans and monkeys using a59Fe tracer and whole-body counting.3. The retention ratio, ferric-Fe; ferrous-Fe was 0.90 in guinea-pigs and 0.33 in monkeys, indicating that monkeys absorb ferrous-Fe preferentially.4. In monkeys retention of Fe from the test diets, as from ferrous ascorbate was lower than that in humans.5. When food-Fe retention was expressed in relation to inorganic-Fe retention the value for retention ratio, food Fe: inorganic Fe in monkeys was similar to that in human subjects.6. The results indicate that the monkey can be used as a model to study Fe absorption from human diets.

Species-Dependent Inhibition of Platelet Aggregation by Adenosine and Dipyridamole: Paradoxical Potentiation in the Rat

1970 ◽  
Vol 23 (01) ◽  
pp. 129-139 ◽  
Author(s):  
R. B Philp ◽  
B Bishop ◽  
Keyword(s):  
Platelet Aggregation ◽  
Guinea Pig ◽  
Adenosine Receptors ◽  
Guinea Pigs ◽  
Human Subjects ◽  
Adenosine Diphosphate ◽  
Inhibition Of Platelet Aggregation ◽  
Rabbit Platelets ◽  
Dependent Inhibition ◽  
Rat Platelets

SummaryPlatelets of cats, rabbits, guinea pigs, rats and human subjects were aggregated with adenosine diphosphate after having been in contact with adenosine or dipyridamole for 5 to 60 min. The species profiles of both agents were the same. Both inhibited aggregation of human and rabbit platelets and the degree of inhibition increased with the time of contact. Neither inhibited aggregation of cat or guinea-pig platelets and both potentiated the rate and extent of aggregation of rat platelets: the degree of potentiation increased with the time of contact. Some reports on the related effects of adenosine and dipyridamole are reviewed and it is suggested that the effects of dipyridamole might be due to an affinity for adenosine receptors.

Effect of clonidine on induced cough and bronchoconstriction in guinea pigs and healthy humans

1994 ◽  
Vol 76 (3) ◽  
pp. 1082-1087 ◽  
Author(s):  
F. O′Connell ◽  
V. E. Thomas ◽  
R. W. Fuller ◽  
N. B. Pride ◽  
J. A. Karlsson
Keyword(s):  
Citric Acid ◽  
Guinea Pigs ◽  
Human Subjects ◽  
Inhibitory Effect ◽  
Healthy Human ◽  
Oral Clonidine ◽  
Healthy Humans ◽  
Human Volunteers ◽  
Dependent Inhibition ◽  
Time To Onset

We examined the effects of the alpha 2-receptor agonist clonidine, administered orally and by inhalation, on citric acid- and capsaicin-induced reflexes in guinea pigs and healthy human subjects. In groups (n = 8-10) of conscious guinea pigs, oral clonidine (10 and 100 micrograms/kg) was without effects, whereas inhaled clonidine (10–1,000 microM) caused a concentration-dependent inhibition of citric acid-induced cough (coughs during 3 min: control, 6.5 +/- 0.9; 1,000 microM clonidine, 1.7 +/- 1.0; P < 0.05) and reflex bronchoconstriction (time to onset of bronchoconstriction: control, 191 +/- 24 s; 1,000 microM clonidine, 317 +/- 33 s; P < 0.05). The inhibitory effect of inhaled clonidine on both reflexes was completely reversed by pretreatment with yohimbine but not with prazosin. In 12 healthy human volunteers, oral clonidine (150 mg) caused a significant fall in supine and erect systolic blood pressure and a significant increase in drowsiness as measured on a visual analogue scale 1 and 2 h after administration. Despite these effects, oral clonidine had no effect on capsaicin-induced cough or reflex bronchoconstriction in humans. In contrast to the effects in guinea pigs, inhaled clonidine (281 microM) had no effect on capsaicin-induced cough or reflex bronchoconstriction in humans. These data suggest that peripheral alpha 2-receptors exert an inhibitory effect on sensory neurotransmission in the guinea pig but not in the healthy human airway, indicating an important difference between the two species.

scholarly journals The fate of the sugar disappearing under the action of insulin

1926 ◽  
Vol 100 (700) ◽  
pp. 32-54 ◽  
Keyword(s):  
Guinea Pigs ◽  
Skeletal Muscles ◽  
Glycogen Content ◽  
Normal Animal ◽  
Liver Glycogen ◽  
Diabetic Animal ◽  
Significant Difference ◽  
Long Time ◽  
Series Of Experiments ◽  
High Level

The apparent disappearance of sugar injected into normal animals has for a long time puzzled physiological investigators (Bang, Meltzer and Kleiner, Palmer, Woodyatt). When insulin was discovered it was apparent that an agent was available by which the normal processes could be exaggerated, and therefore more easily studied. It was soon shown that the administration of sugar and insulin to the diabetic animal resulted in an increased combustion of carbohydrate and the accumulation of glycogen in the depôts. When, however, attempts were made to trace the fate of the sugar which disappears from the blood of the normal animal under the influence of an injection of insulin, difficulties were encountered. McCormick and Macleod (1) studied the effect of insulin on the glycogen reserves of rabbits which had been starved and treated with epinephrin. In some of the experiments glucose was administered subcutaneously during the period of action of insulin. No significant difference between the glycogen content of the muscles of the control animals and of those which received insulin was observed. The glycogen of the livers of the insulin-treated animals was slightly less than that of the control animals. Macleod (2) concluded from these experiments “that less glycogen is deposited both in the muscles and the liver when insulin is given along with sugar to previously starved animals than when the same amounts of sugar are given alone.” In the experiments of Dudley and Marrian (3), in which the effect of insulin on the liver glycogen of mice was studied, a much smaller amount of glycogen was found in the livers of the animals which received insulin than in those which served for controls. In another series of experiments in which insulin was administered to rabbits which had been previously fed on a carbohydrate rich diet, the glycogen content of the liver and skeletal muscles of the insulin-treated animals was again much less than that of the control animals. In both series of experiments the animals were killed after convulsions had supervened. The experiments of Babkin (4) are similar to those of McCormick and Macleod. In some of his experiments Babkin kept the blood sugar of the rabbits at a high level by the administration of sugar. He found no increase in glycogen after insulin. Kuhn and Baur (5), in a study of the effect of insulin on the glycogen content of the skeletal muscles of rabbits and guinea-pigs, found that, after insulin convulsions, the glycogen had practically disappeared from the muscles of these animals. They are undecided as to whether the depletion of glycogen is a primary effect of insulin or is to be attributed to the convulsions.

scholarly journals A Study of the Single Compartment Tracer Kinetic Model for the Measurement of Local Cerebral Blood Flow Using 15O-Water and Positron Emission Tomography

1987 ◽  
Vol 7 (1) ◽  
pp. 13-20 ◽  
Author(s):  
Sanjiv S. Gambhir ◽  
Sung-Cheng Huang ◽  
Randall A. Hawkins ◽  
Michael E. Phelps
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Data Collection ◽  
Human Subjects ◽  
Compartment Model ◽  
Distribution Volume ◽  
Single Compartment ◽  
Positron Emission ◽  
Single Compartment Model ◽  
Collection Time

The effects of varying the data collection time on the calculation of cerebral blood flow and distribution volume via the integrated projection technique were studied in four human subjects. The significance of these results in terms of the limitations of the single compartment model for 15O-water was explored using computer simulations. The simulations helped to account for causes for the variations seen in blood flow and distribution volume as a function of the data collection time. Two different compartmental models were explored for better quantitation of blood flow and distribution volume.

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