bluuebunny/crossref_metadata_2025_split huggingface dataset:
Uptake of Dopamine by the Storage Granules of the Adrenal Medulla in Vitro
Authors: Bertler ÅKe , Hall Gösta , Hillarp Nils‐Åke , Rosengren Evald 
Published: December 2008

AbstractLarge amounts of dopamine are taken up by the amine storage granules of the cow adrenal medulla when the granules are incubated at + 31° in a solution containing dopamine. At this temperature the amine accumulates even against an apparent concentration gradient but at 0° only small amounts — if any at all — are incorporated. The amine seems to be bound in the granules but is released on osmotic lysis of the granules.
The Effect of Histamine on the Uptake of35S by the Duodenal Mucosa of Guinea Pigs
Authors: Ball P. , Häkkinen I. , Hartiala K. 
Published: December 2008

AbstractThe purpose of the work was to find out to what degree the effect of promoting the uptake of35S was dependent upon free access of acid to the duodenal lumen. The pylorus was ligated in 32 young male guinea pigs. Histamine in a dose of 3 mg/kg body weight was administered subcutaneously as the35S sulphate given immediately after the operation. The animals were sacrified 24 hours later. It was found that the uptake of35S sulphate was increased both in the duodenal mucosa and in the underlying“stroma”. The results would indicate that in the guinea pig histamine stimulates the synthesis of mucus in the duodenum also under conditions where the effect of acid has been eliminated.
Urinary Excretion Patterns for Substances with Simultaneous Secretion and Reabsorption by Active Transport
Authors: Berglund Fredrik 
Published: December 2008

AbstractSubstances, which are actively secreted and reabsorbed by the renal tubules, show different excretion patterns. Except for potassium, they all follow a“secretion proximal” pattern, i. e. secretion takes place at a site proximal to reabsorption or through identical cells. Thiosulfate, creatinine and uric acid are typical examples. — For thiosulfate, secretion Tm = reabsorption Tm. At low plasma levels its clearance is low; at higher levels the clearance equals glomerular filtration rate. — For creatinine, secretion Tm > reabsorption Tm; its clearance is low at low plasma levels, but exceeds glomerular filtration rate at high levels. The dependence of“endogenous creatinine clearance” on glomerular filtration rate and renal blood flow is discussed. — A similar pattern is shown by uric acid in the rabbit. In man, uric acid reabsorption Tm > secretion Tm, the net result being reabsorption at all plasma levels.
Further Observations on Anaphylactic Mast‐Cell Changes in the Nasal Mucosa of Guinea Pigs in Vivo
Authors: Boréus Lars Olof 
Published: December 2008

AbstractThe anaphylactic reactions of tissue mast cells were quantitatively studied in the nasal mucosa of anaesthetized guinea pigs in vivo. Intra‐arterial challenge with antigen produced extensive disappearance of the mast cells, as well as anaphylactic shock symptoms, in animals sensitized passively with rabbit anti‐ovalbumin or actively by intranasal application of ovalbumin. ACTH and cortisone in high doses did not prevent the development of active anaphylaxis, nor did they significantly alter the average mast‐cell population of the tissue. Moreover, the cell reaction to antigen was not antagonized by pretreatment with these hormones. Heating of the animal prior to challenge, and prolongation of the injection time diminished the anaphylactic mast‐cell reaction and the intensity of shock symptoms. The“missing” mast cells were seen to reappear in about 7 weeks. On administration of antigen in vivo they again displayed a strong disappearance reaction.
Studies on the Peripheral Circulation and Metabolism in Man I. Oxygen utilization and lactate‐pyruvate formation in the legs at rest and during exercise in healthy subjects
Authors: Carlson Lars A. , Pernow Bengt 
Published: December 2008

AbstractArterial and femoral venous oxygen and lactate‐pyruvate was studied at rest, during and after leg exercise in 15 healthy human males. At rest in the supine position the femoral venous oxygen saturation was 53–81 per cent. A few minutes after starting work, the venous oxygen saturation was 22–42 per cent and a slight but steady decrease was observed on continued work. Five minutes after work, the venous oxygen saturation was significantly higher than at rest before work. The pH of the femoral venous blood decreased from mean 7.41 to 7.25 at maximal load. The venous lactate rose during exercise to 4.45–8.66 mM/liter and the venous‐arterial lactate difference to mean 0.85 mM/liter at a heart rate of 160–187/minute. After exercise the lactate decreased successively in most cases but had even 30 min later not reached the initial level before work. The venous pyruvate concentration was 0.09‐0.15 mM/liter at rest, and increased successively during exercise to 0.22‐0.35 mM/liter at the highest loads. A further increase in pyruvate was obtained during the first minutes after work. The increase in“excess of lactate”, as calculated from the lactate‐pyruvate ratio, during exercise was practically parallel to that in total lactate, indicating that during work the total lactate is a good indicator of the adequacy of oxygen supply to the tissues. After exercise, however, there was a discrepancy between the total and excess of lactate, the latter decreasing much more rapidly. No difference was obtained between older and younger subjects concerning increase in pulse rate or changes in oxygen saturation and blood lactate‐pyruvate during exercise. After work lactate decreased more slowly in the older subjects than in the younger.
Modifications of the Febrile Response to Pyrogen by Hypothalamic Heating and Cooling in the Unanesthetized Dog
Authors: Andersen H. T. , Hammel H. T. , Hardy J. D. 
Published: December 2008

AbstractExperiments have been carried out with the aim of obtaining additional information on the mode and site of action of pyrogens. On the assumption that these agents act on the thermally sensitive cells of the anterior hypothalamus by raising the“set point” for physiological temperature regulation to a higher level, it was planned to counteract their effect by heating this region of the hypothalamus with 3.7 megacycle radio frequency energy between implanted thermodes, or enhance their effect by cooling the same area by circulating water through the thermodes. Temperatures were measured by means of thermocouples inserted into the thermodes. The rectal and the skin temperatures were also recorded by means of thermocouples. Fever was induced in the animals by intravenous administration of a pyrogenic polysaccharide obtained from Pseudomonas. The body temperature started to increase 30–45 minutes after the injection and usually remained at the elevated level for 3 hours or more. Heating of the hypothalamus was performed 1) immediately after administration of pyrogen, 2) while the fever developed and 3) when the fever condition was maximal. In the first case, the fever failed to develop, in the second instance, the rise in rectal temperature was stopped, and in the third event, thermoregulatory responses similar to those obtained with the same technique at normal body temperature were elicited. In the experiments in which the pyrogenic action was enhanced by hypothalamic cooling a“hyperfever” was produced.
The Effect of Cobalt Ions on the Biosynthesis of Hemoglobin by Rabbit Reticulocytes in Vitro
Authors: Eriksen Leif , Eriksen Nora , Haavaldsen Synnöve 
Published: December 2008

AbstractThe effect of cobalt ions on the biosynthesis of hemoglobin by rabbit reticulocytes in vitro has been studied. It is shown that cobalt ions in concentrations of approximately 10‐3 M almost completely inhibit the formation of heme, while the formation of globin is unaffected or slightly stimulated. The inhibiting effect on heme formation is found to be due to inhibition of the formation of the tetrapyrrolic intermediates in heme formation, while the conversion of the 8 carboxylic intermediate by stepwise decarboxylation and finally dehydrogenation and iron incorporation is unaffected. The implications of the above findings for the understanding of the effect of cobalt ions on the erythropoiesis are discussed, and it is suggested that the polycythemia induced by cobalt ions may be due to a toxic effect of the metal on hemoglobin formation with a secondary stimulation of red cell formation. The possibility that cobalt may exert a directly stimulating effect on the formation of erythropoietine is not, however, excluded.
Evidence for Energy‐Requiring Processes in Histamine Release and Mast Cell Degranulation in Rat Tissues Induced by Compound 48/80
Authors: Diamant Bertil , Uvnäs Börje 
Published: December 2008

AbstractHistamine release from rat lung tissue and degranulation of rat mesentery mast cells were produced in vitro by Compound 48/80. Both processes were shown to be blocked by anoxia and by inhibitors of oxidative phosphorylation. Preincubation with glucose counteracted this inhibition. The results indicate that histamine release and mast cell degranulation require energy which can derive from glucose metabolism.
Studies of the Effect of X‐Rays on the Glucuronide Synthesis and β‐Glucuronidase Activity in the Duodenal Mucous Membrane of the Rat
Authors: Hartiala K. , Näntö V. , Rinne U. K. 
Published: December 2008

AbstractIn a series of previous experiments we have studied the effect of local X‐ray irradiation on the glucuronide conjugation capacity and on the p‐glucuronidase activity of the liver and gastric mucosa. According to these studies the sensitivity of these tissues towards irradiation is different. These studies also show that the changes in the glucuronide formation capacity and the β‐glucuronidase activity are not parallel which is taken as a further indication that the β‐glucuronidase enzyme is not involved in the synthesis of glucuronide‐conjugates. In the present work we have studied the glucuronide conjugation and β‐glucuronidase activity of rat duodenal mucosa after local X‐ray irradiation.
In Vivo Incorporation of 69Fe into Nonhem Iron and Hemoglobin of Red Blood Cells
Authors: Falbe‐Hansen Iens , Lothe Kari 
Published: December 2008

AbstractFalbe‐Hansen, I. and K. Lothe. In vivo incorporation of 50Fe into nonhem iron and hemoglobin of red blood cells. Acta physiol. scand. 1962. 54. 97–104. – The incorporation of 59Fe into nonhem iron and hemoglobin iron of circulating erythrocytes has been followed in rabbits. The experiments indicate that nonhem iron represents an intermediate step in the passage of iron from transferrin to hemoglobin. Nonhem iron is also present in the later stages of erythrocyte life, but in a metabolically inactive state. By electrophoresis three iron‐containing fractions have been separated, one of which is radioactive. It is suggested that this radioactive fraction represents a shortlived step in the iron transport system. One of the inacative fractions has an electrophoretic migration velocity similar to that of ferritin.
Effects of Different Types of Vasodilator Mechanisms on Vascular Tonus and on Transcapillary Exchange of Diffusible Material in Skeletal Muscle
Authors: Renkin Eugene M. , Rosell Sune 
Published: December 2008

AbstractPressure‐flow curves, representing various states of vascular tonus were obtained in isolated skeletal muscles of dogs and cats perfused with blood at constant flow. The arteriovenous (A‐V) extraction of rubidium‐86 was also continuously recorded. Metabolic vasodilatation and vasodilatation due to inhibition of the activity in the vasoconstrictor nerves induced a decrease of vascular tonus and an augmented blood‐tissue transport. Vasodilatation due to excitation of cholinergic vasodilator nerves produced a decrease in peripheral resistance amounting to about 70 per cent of the decrease caused by metabolic vasodilatation. Vasodilator nerve activity did not produce any consistent change in blood tissue transport. It is considered that vasodilator nerve activity produces an arteriolar dilatation, whereas vasodilatation due to inhibition of vasoconstrictor nerve impulses or followed by muscular contraction induces relaxation of smooth muscles in both arterioles and precapillary sphincters
Intramuscular, Rectal and Oesophageal Temperature During Exercise
Authors: Karvonen Äikäs E. , Piironen P. , Ruosteenoja R. 
Published: December 2008

AbstractTemperature recordings were made from the vastus lateralis of the m. quadriceps femoris, from the m. biceps brachii, from oesophagus and from rectum, before, during, and after exercise on a bicycle ergometer, using the loads of 900, 1,200 and 1,500 kpm/min. Three adult males served as subjects. The temperature of the vastus lateralis at rest was 33.5–35d̀ C. The beginning of the work was followed by a rise which levelled after about 15 min. The final temperatures were 37.8–39.7d̀ C, corresponding to the load. The changes from the temperature of the resting biceps brachii, 34.5–36.0d̀ C, were slight, less than 0.5d̀ C. The oesophageal temperature showed an initial fall of 0.1–0.4d̀ C during the first minutes, followed by a rise; the temperature levelled within 15 min to 37.8—39.0d̀ C, corresponding to the work load. The rectal temperature failed to show an initial fall, rose steadily throughout the 30 min exercise period. After exercise, the oesophageal temperature returned to resting values in half an hour, while the rectal temperature showed a steady fall over an hour. During the first minutes of exercise, the active muscles gain heat from the rest of the body.
Catecholamine Excretion during Mental Work as Modified by Centrally Acting Drugs
Authors: Frankenhaeuser Marianne , Post Birgitta 
Published: December 2008

Abstract— Experiments were performed to determine (1) whether changes in catecholamine excretion are sensitive indicators of the state of mild stress induced by performing psychological tasks, and (2) whether centrally acting drugs would modify such changes. Adrenaline excretion was shown to be significantly higher (1) during testing than during inactivity, and (2) after intake of metamphetamine (10 mg) than after pentobarbitone (200 mg). No effects on noradrenaline excretion were demonstrated. Both drugs induced marked changes in mood, but with one exception (verbal performance under pentobarbitone) changes in performance were not found.
Quantitative Determination of Uveal Blood Flow in Rabbits
Authors: Bill Anders 
Published: December 2008

AbstractIn rabbits, the uvea is drained essentially by four vortex veins which are nearly equal in size. The veins communicate within the eye through large anastomoses. Investigations were carried out to discover whether the blood flow through the uvea may be determined as the flow from one opened vortex vein multiplied by the number of veins. The results indicate that such a procedure is adequate at intraocular pressures of 10—15 mm Hg or more and normal or low extraocular vortex venous pressures and uveal blood flow rates. It appears that the adequacy of the procedure is due to the fact that under such conditions the pressure in the proximal part of the uveal veins is little different from the intraocular pressure. It also appears that the resistance in the veins draining the uvea may be caused, in part, by collapse of the vessels provided the pressure and flow requirements mentioned are fulfilled.
Studies of the Heated Thermocouple Principle for Determinations of Blood Flow in Tissues
Authors: Bill Anders 
Published: December 2008

AbstractA study was made in models of some of the factors influencing the adaptability of the heated thermocouple principle for blood flow determinations in tissues. The apparent thermal conductivity was determined with conventional technique. The tissue blood flow was simulated by flow of water in polyethylene tubes embedded in gelatin blocks and through holes in gelatin blocks. The findings indicate that there can be no standard type of relationship between the apparent thermal conductivity increment and the flow in any tissue into which the probe is blindly introduced. It is concluded from the results that the probe is most suitably placed when influenced only by flow in great numbers of capillaries and very small veins. For quantitative determinations the probe has to be standardized in each experiment. Standardizations will apply only under certain conditions, which are discussed.
The Metabolism of 1‐C14‐Palmitic Acid Labeled Chylomicrons in Rats
Authors: Olivecrona Thomas 
Published: December 2008

Abstract1‐C14‐palmitic acid labeled chylomicrons have been injected to carbohydrate‐fed rats and liver, plasma, adipose tissue and carcass activities followed. There was initially more activity going to the liver and adipose tissue and less to the carcass than when FFA was injected. However, although the mechanisms of uptake of FFA and chylomicrons differ fatty acids injected in either form soon enter the same pools and share the same fate. No major difference could be found in the specific activities of samples from epididymal, perirenal and subcutaneous adipose tissue.
Lactic Acid Production and Adrenaline Reversal in Experiments on Isolated Smooth Muscle
Authors: Mohme‐Lundholm Ella 
Published: December 2008

AbstractIn experiments on isolated muscle preparations from rabbit stomach adrenaline had a contracting effect and increased the lactic acid content. Lactic acid was determined with an enzymatic method. After treatment with dibenamine, the preparations were relaxed by adrenaline. The lactic acid production remained unchanged. Adrenaline reversal after dibenamine was interpreted as a selective inhibition by dibenamine of the contracting effect of adrenaline, following which the relaxing and lactic acid stimulating action was evidence.
Electrolyte Effect of Cardiac Glycosides on Dog's Heart‐Lung Preparation
Authors: Areskog N.‐H. 
Published: December 2008

AbstractThe electrolyte effect of the rapid acting heart glycoside convallatoxin was investigated on heart‐lung preparations of dog, labelled with 42K and 24Na. Total concentrations of plasma potassium and sodium were determined by flame photometry. The radioactivity of plasma, heart lymph and myocardial samples was determined by gamma spectrometry. A net loss of potassium from the myocardium was induced by the glycoside but there was not a corresponding loss of 42K. This means that isotopic equilibrium was not attained in spite of an ‘equilibration’ time of 60—90 min and the conclusion is drawn that the glycoside mainly affected a part of the intracellular myocardial potassium which has a relatively slow exchange rate. The changes in heart lymph were principally the same as in plasma. No significant changes of the sodium balance due to the glycoside action was found.
An Automatic Bubble Flow Meter
Authors: Ulfendahl Hans R. , Vogeler Ingemar 
Published: December 2008

AbstractThe construction of an automatic bubble flow meter for measurement of arterial or venous blood flow is described. The blood passes through a plastic tubing kept at a constant temperature by a water thermostat. An air bubble is automatically injected into the tubing and the passage of the bubble is detected by two phototransistors. The phototransistor circuit is favourable because of low sensitivity of external pickup. The blood flow is correlated to either the number of bubbles per minute or to the reciprocal value of the passage time of one bubble. In both cases a good linear relationship exists between a flow of 15 and 300 ml per minute. The flow resistance is 0.03 mm Hg/ml/min.
Hematocrit and Hemoglobin Concentration in Venous Blood Drained from the Outer Cortex of Cat Kidney
Authors: Ulfendahl Hans R. 
Published: December 2008

AbstractThe cell separation theory of Pappenheimer and Kinter for the intrarenal blood flow was studied in cats by measuring red cell concentration in subcapsular veins on the renal surface and in arterial blood. The venous blood, taken from the subcapsular vein, was assumed to be drained from the outer parts of the cortex. Hematocrit values and hemoglobin concentrations were significantly higher at blood pressures above 75 mm Hg in blood from the subcapsular veins than in arterial samples. Below 75 mm Hg, no difference was found. Control experiments showed that the most probable explanation of the high red cell concentration in blood draining the outer part of the cortex was the occurrence of an intrarenal separation of red cells and plasma, but the extent of separation was not clear.
Comparison Between the Effects of Glucose and Sodium Succinate on the in Vitro Release of Histamine from Guinea‐pig and Rat Lung Tissue1
Authors: Diamant Bertil 
Published: December 2008

AbstractHistamine release elicited under nitrogen anoxia by antigen from sensitized guinea‐pig lung tissue, and by compound 48/80 from non‐sensitized rat lung tissue, was enhanced by the presence of glucose but not by that of sodium succinate. In the presence of oxygen, sodium succinate as well as glucose enhanced antigen‐induced histamine release from guinea‐pig lung tissue. In contrast, histamine release from rat lung tissue induced by antigen, as well as by compound 48/80, was not enhanced by sodium succinate in the presence of oxygen, whereas glucose was effective in both reactions. Possible reasons for this species difference are discussed in the light of the supposition that the histamine‐releasing reactions investigated depend on adequate utilization of energy‐yielding substrates and of high‐energy compounds.
The Effect of Electrical Stimulation in Nucleus Ruber on the Response to Stretch in Primary and Secondary Muscle Spindle Merents
Authors: Appelberg Bo 
Published: December 2008

AbstractIn cats anesthetized with Nembutal the activity in muscle spindle afferents was recorded in thin dorsal root filaments. The conduction velocity of each fibre recorded from was determined. The value of 72 m/sec was used for separating primary and secondary afferents. The effect of electrical stimulation in the red nucleus on the adapted discharge to a steady stretch of the muscle under study was tested. It appeared that while the activity in primary afferents was as a rule strongly inhibited, the secondary discharge was only slightly or not at all influenced by the rubral stimulus. The dynamic burst of activity in primary afferents seen during the application of a slow extension of the muscle was also studied. The rubral stimulation as a rule caused an increase in the dynamic response although the static discharge was inhibited before as well as after the application of stretch. The results are discussed in relation to anatomical and physiological knowledge about muscle spindles. The conclusion is reached, that the red nucleus has an inhibitory influence upon the gamma supply to nuclear chain intrafusal fibres, but does not affect the motor innervation of the nuclear bag fibres.
Effects from the Pyramidal Tract on Spinal Reflex Arcs
Authors: Lundberg A. , Voorhoeve P. 
Published: December 2008

AbstractThe effect of stimulation of the sensorimotor cortex on spinal reflex arcs was investigated in cats with intracellular recording from motoneurones and with conditioning of monosynaptic reflexes. Stimulation of cortex enhances the following synaptic actions in motoneurones: Ia inhibitory, Ib reciprocal, FRA reciprocal, FRA inhibitory to flexor and cutaneous excitatory to extensor motoneurones. The effects are mediated by the pyramidal tract which presumably exerts an excitatory action on interneurones of reflex arcs. Stronger stimulation of cortex evokes synaptic actions in motoneurones with excitatory action dominating in flexor and inhibitory in extensor motoneurones. There was frequently evidence of mixed excitatory and inhibitory effects in extensor motoneurones and inhibitory action in flexor motoneurones was also found. It is suggested that these actions on motoneurones are due mainly to activation of interneurones of spinal reflex arcs.