bluuebunny/crossref_metadata_2025_split huggingface dataset:
On the Nervous Factors Controlling Respiration and Circulation during Exercise Experiments with curarization
Authors: Asmussen Erling , Johansen S. H. , Jørgensen Mogens , Nielsen M. 
Published: December 2008

AbstractIn the steady state of work on a bicycle ergometer repeated i.v. injections of (+) tubocurarine produced a decrease in handgrip strength. In spite of this the intensity of work was maintained constant for 20 to 30 min. During this time pulse rate and blood pressure increased slightly and irregularity but the ventilation increased, both absolutely and in relation to the oxygen uptake, by up to about 50 %. The cardiac output was uninfluenced by the curarization. By adding CO2 to the inspired air the alveolar PCO2 was maintained at the normal exercise level. It is therefore assumed that all the known humoral factors controlling respiration in exercise must have been normal. The greatly increased ventilation must consequently have been caused by some nervous factors. The origin of these factors, whether central or peripheral, is discussed on the background of earlier experimental findings. A tentative explanation, based on the assumption that bicycle‐work is performed by the mediation of the gamma‐loop, is suggested. According to this the“nervous factor” of respiratory regulation in exercise may be the feed‐back to the reticular formation of afferent impulses from the muscle spindles.
The Effects of Surfactants on the Potential, Short‐circuit Current, and Ion Fluxes Across the Isolated Frog Skin
Authors: Webb George D. 
Published: December 2008

AbstractIt has been shown previously that ionic surface active agents (surfactants) depolarize nerve and muscle membranes and the isolated frog skin. The isolated frog skin was used in the present studies. Measurements of skin potential, short circuit current, and of Na, K, and Cl fluxes were made to determine the relative roles of inhibition of active Na transport and increases in passive ion permeability in producing the depolarization. The electrical data were in agreement with the flux data in demonstrating that lower concentrations of ionic surfactants (0.5 mM) generally inhibit the active Na transport process but have little effect on passive ion permeability. At higher concentrations (2 mM or more) surfactants produce an increase in permeability in addition to inhibiting the“Na pump”. The outside surface of the frog skin was more sensitive to the surfactants than was the inside.
Concentration and Turnover of the Free Fatty Acids of Plasma and Concentration of Blood Glucose during Exercise in Horses
Authors: Carlson Lars A. , Froberg Sven , Persson Sune 
Published: December 2008

AbstractThe concentration of FFA and glycerol in plasma and of glucose and lactate in blood was studied in 5 horses during exercise. The turnover of FFA was also determined. During exercise the efflux of FFA from plasma as well as the mobilization of FFA into plasma was increased. The glycerol concentration generally increased while the concentration of glucose fell. This decrease of glucose was very pronounced in 2 of the horses. The lactate concentration showed no consistent changes. When epinephrine was infused into 2 horses the concentration and the turnover of FFA as well as the concentration of glycerol increased. The concentration of glucose fell slightly while the lactate concentration increased significantly in response to adrenaline.
On the Competition between Metabolic Vasodilatation and Neurogenic Vasoconstriction in Skeletal Muscle1
Authors: Kjellmer I. 
Published: December 2008

AbstractUsing a plethysmographic method combined with recording of blood flow and, at times, recording of the volume of blood in the calf of the cat with an isotope technique, the responses of the resistance vessels, of the capillary filtration coefficient and of the capacitance vessels were studied when the vessels were subjected to the antagonistic influences of muscular exercise and vasoconstrictor fibre activity.At the higher frequencies of stimulation used sympathetic activation caused an equally marked reduction of blood flow during exercise as during rest, but during exercise the response of the resistance vessels subsided within a few minutes to become steady at a level only a little above starting level despite continued stimulation. The capillary filtration coefficient, already increased during exercise, was affected, and then increased still further only when the sympathetic were stimulated at such frequencies as impeded blood flow markedly. Sympathetic stimulation during exercise increased the tone of the capacitance vessels—a response that did not weaken at all so soon as that of the resistance vessels.It is concluded that the resistance vessels and particularly the precapillary sphincters are more sensitive to vasodilator metabolites locally released during exercise than to the vasoconstrictor fibre supply, while the reverse is true for the capacitance vessels.
Coronary Collateral Blood Flow in Relation to the Mass of Ischemic Myocardium, Studied with Krypton85
Authors: Johansson Börje , Linder Erland , Seeman Torsten 
Published: December 2008

AbstractBlood flow in the ischemic region during acute coronary occlusion in anesthetized open chest dogs was studied by external recording of wash out curves after intracoronary administration of Kr85. Flow values were satisfactorily well reproducible in 29 double determinations. Collateral blood flow ranged from 6 to 44 ml/min × 100 g tissue. The magnitude of flow was inversely related to the weight of the ischemic region in 14 of 20 dogs. In 6 dogs with the lowest flow values this correlation was only slightly indicated. Arterial occlusion did not seem to affect flow in adjacent nonischemic myocardium. The potential advantages of the present technique for the study of collateral blood flow are discussed in comparison with other methods.
The Metabolism of Fatty Acids in the Rat VI. Arachidonic Acid
Authors: GÖRANSSON GÖRAN 
Published: December 2008

AbstractGöransson, G. The metabolism of fatty acids in the rat. VI. Arachidonic acid. Acta physiol. scand. 1965. 64. 1–5. ‐H3‐labeled arachidonic acid and C14‐labeled palmitic acid were simultaneously injected into male rats. Arachidonic acid was preferentially incorporated into liver phospholipids as might be expected from the preponderance of this fatty acid in liver phospholipids as compared to glycerides. Initially, the labeled arachidonic acid and the labeled palmitic acid were oxidized at similar rates but at later times more arachidonic acid than palmitic acid was recovered from the whole animal. This may be explained by the preferential incorporation of arachidonic acid into phospholipid in combination with the low turnover rate of the phospholipids, especially those containing essential fatty acids. The pattern of label in the blood glycerides closely resembled that in the corresponding liver fraction.
The Steady State and Endogenous Respiration in Neuron and Glia
Authors: HYDÉN HOLGER , LANGE PAUL W. 
Published: December 2008

AbstractHydén, H. and Lange, P. W. The steady state and endogenous respiration in neuron and glia. Acta physiol. scand. 1965. 64. 6–14. –The oxygen consumption of individual, surviving nerve cells and glial cells was studied for two hours periods. An extrapolation procedure was worked out which permitted the determination of the oxygen consumption rate in the steady state in vivo and the substrate amount for endogenous respiration. The oxygen consumption rate of the neurons exceeded that of the glia by at least ten times in the steady state. The values obtained were used for calculation of the amount of glucose per nerve cell which was found to be 5 per cent of the dry weight of the cell corresponding to a 70 mM glucose solution. The amount of glucose in glia is 5 to 10 times lower than that of nerve cells. Addition of glucose or β‐hydroxybutyrate to nerve cells having respired without exogenous substrate for two hours highly increased the respiration rate. In neurons with increased RNA synthesis and respiratory enzyme activities, the respiration rate and substrate level were low.
Some Mechanical Aspects of an Intestinal Smooth Muscle
Authors: ÅBERG A. K. G. , AXELSSON J. 
Published: December 2008

AbstractÅberg A. K. G. and J. Axelsson. Some mechanical aspects of an intestinal smooth muscle. Acta physiol. scand. 1965. 64. 15–27. – Atonic pieces of taenia coli muscle were obtained with the aid of adrenaline which abolishes spontaneous spike discharge. As reference length the in vitro length at 37° C, relaxed with adrenaline, was used. Lo (isometric) is arbitrarily defined as the greatest length of an inactive muscle when the force applied to straigthen it does not exceed 50 dynes. At this length the muscles were found to develop maximum tension. Lo (isotonic) is the preloaded length of a relaxed muscle. These conditions gave results which were repeatable with reasonable statistical accuracy, other conditions gave less reproducible results. Force‐velocity curves obeying Hill's equation (P+a) (v + b) = (Po + a) b were obtained. Maximum velocity of shortening of an unloaded muscle was extrapolated to 30 per cent of Lo/sec. Velocity of shortening appeared related to the ratio Po: P. Rate of tension development was related to muscle length and resting tension, with a maximum at 130 to 180 per cent of Lo. The highest rate measured was 2,800 dynes/sec. Maximum physical work was performed with constant load of about 30 per cent of Po. Maximum shortening of the muscles under 100 dynes tension varied from 60–80%. The results are discussed in relation to other types of muscle.
The Effect of Removing and Readmitting Glucose on the Electrical and Mechanical Activity and Glucose and Glycogen Content of Intestinal Smooth Muscle from the Taenia Coli of the Guinea Pig
Authors: AXELSSON J. , HÖGBERG S. G. R. , TIMMS A. R. 
Published: December 2008

AbstractAxelsson, J., S. G. R. Högberg and A. R. Timms. The effect of removing and readmitting glucose on the electrical and mechanical activity and glucose and glycogen content of intestinal smooth muscle from the taenia coli of the guinea‐pig. Acta physiol. scand. 1965. 64. 28–42. The effects of changing the glucose concentration in the bathing solution on frequency of spike discharge, membrane potential, and on the mechanical responses is described quantitatively and related to tissue content of glucose and glycogen. Removing glucose increases and readmitting inhibits spike discharge. The membrane potential depends on carbohydrate metabolism for its maintenance. Its dependence is, however, quantitatively or qualitatively different from that of the contractile mechanism. Spike discharge of high frequency persisted for hours after the mechanical response was abolished. In glucose‐free solution the mechanical response fell in parallel with tissue content of glycogen. In normal solution there was no correlation between tension and glycogen content.
Renal Clearances of Inulin, Polyfructosan‐S and a Polyethylene Glycol (PEG 1,000) in the Rat
Authors: BERGLUND FREDRIK 
Published: December 2008

AbstractBerglund, F. Renal clearance of inulin, polyfructosan‐S and a polyethylene glycol (PEG 1,000) in the rat. Acta physiol. scand. 1965. 64. 238–244. The renal clearances of inulin, polyfructosan‐S and PEG 1,000 were measured in the rat by means of a constant infusion technique. The inulin/PEG 1,000 clearance ratio in 10 rats averaged 0.81, and polyfructosan‐S/PEG 1,000 ratio in 10 rats averaged 0.87. The clearance ratios differed signicantly from unity and were not influenced by phlorizin. The restricted filterabliity of the two polysaccharides in the rat is attributed to the pore size of the glomerular membrane, and a relationship between pore size and animal size is suggested.
Influence of Passive and Active Heating on the Temperature Regulation of Man
Authors: NIELSEN BODIL , NIELSEN MARIUS 
Published: December 2008

AbstractNielsen B. and M. Nielsen. Influence of passive and active heating on the temperature regulation of man. Acta physiol. scand. 1965. 64. 323–331. – The effect of passive heating through diathermia on thermoregulatory responses is compared to the effect of active heating by exercise on a Krogh bicycle ergometer in 2 human subjects. The rate of heat production in the two conditions was of the same magnitude (about 5 times the basal heat production). – The rectal temperature increased with passive heating to about the same level as during active heating and appeared, within limits, to be independent of the environmental temperature. At the same mean skin temperature conductance and sweat rate with passive and active heating were much higher than during normal rest. But in the two conditions of heating the rates of skin blood flow were equal and the rates of sweating not much different, when compared at the same mean skin temperature. The results indicate, therefore, that the main stimulus for the increase of heat dissipation during the steady state of work caused by the work itself, is the increased internal temperature, and that the changes in heat dissipation during work caused by changes in the environmental temperature within wide limits are mainly due to changes in skin temperature.
Electrophysiological Investigation of the Gustatory Effect of Ethyl Alcohol II: A Single Fibre Analysis in the Cat
Authors: HELLEKANT GÖRAN 
Published: December 2008

AbstractHellekant, G. Electrophysiological investigation of the gustatory effect of ethyl alcohol. II: A single fibre analysis in the cat. Acta physiol. scand. 1965. 64. 398–406.–The response of single gustatory fibres of the chorda tympani in the cat to alcohol has been recorded and compared to the responses to NaCI, sucrose, acetic acid and quinine. Alcohol ewoked a response in all gustatory fibres tested. In regard to their response pattern two principal groups of fibres have been observed. In the first group alcohol produces an initial decrease of the spontaneous activity followed by a delayed and moderate increase. When the tongue is rinsed with water after the alcohol there is a strong burst of impulses. In the second group alcohol produces an immediate response characterized by a moderate increase in impulse frequency. A subsequent application of water does not give rise to any burst of impulses in this group but brings the impulse frequency back to the resting level. An analysis of the response pattern of single gustatory fibres revealed also that the first group of fibres are predominantly sensitive to water, acid and quinine, but is usually not stimulated by NaCl. The second group is generally activated by salt.
Effects of Ganglionic Blocking Drugs on Blood Glucose, Amino Acids, Free Fatty Acids and Catecholamines at Exercise in Man
Authors: CARLSTEN ARNE , HÄGGENDAL JAN , HALLGREN BO , JAGENBURG RUDOLF , SVANBORG ALVAR , WERKÖ LARS 
Published: December 2008

AbstractCarlsten, A., J. Häggendal, B. Hallgren, R. Jagenburg, A. Svanborg and L. Werkö. Effects of ganglionic blocking drugs on blood glucose, amino acids, free fatty acids and catecholamines at exercise in man. Acta physiol. scand. 1965. 64. 439–447. – The influence of exercise of submaximal load on the arterial concentration of catecholamines, free fatty acids (FFA), and amino acids was studied in 6 young healthy men. The noradrenaline (NA) level increased as a rule successively but the low adrenaline (A) level was unchanged. After 14–18 min of work there was no change in the total FFA level, but among the individual FFA the percentage of stearic and oleic acid decreased, whereas that of palmitic, palmitoleic and linoleic acid increased. The total amino nitrogen level increased and among the individual amino acids there was a marked elevation in alanine. When the exercise was performed during the infusion of ganglionic blocking drugs the increase in NA was abolished or less marked but the changes in the arterial concentrations of glucose, lactic acid, pyruvic acid, amino acids and FFA were similar as without drugs. These results indicate that the role of the sympathetic nervous system is of minor importance for the regulation of the free fatty acid level in serum during exercise.
The Kidney Cortex Slice Technique as a Model for Sodium Transport In Vivo A Qualitative Evaluation
Authors: Bojesen E. , Leyssac Paul P. 
Published: December 2008

AbstractBojesen. E. and P. P. Leyssac. The kidnty cortex slice technique as a model for sodium transport in vivo. A qualitative evaluation. Acta physiol. scand. 1965, 65, 20–32. — Morphologically the tubules of slices incubated at 37°C present thrmselves as occluded with greatly swollen cells in contrast to the open ancl distended tubules with well‐defined and cubic cells in vivo. The cellular sodium and potassium concentrations of incubated slices differ markedly from the calculated intra‐cellular concentrations in the functioning cells, which were found to be: 4–15 μeq Na+/g cellular Water and 123–135 μeq K+/g cellular water. Efflux studies on slices incubated with radioactive sodium did not disclose any active component when flushed with Ringer solutions of different electrolyte composition and temperatures, or in the presence of metabolic inhibitors. At a sulfate concentration of 6 mM, at which concentration the volume of distribution was equal to that of sodium, the curves on the log. of efflux rates of the two species of ions were parallel during eluation of almost the entire amount.The results suggest that at least a major fraction of sodium in cortical slices is in diffusion equilibrium with the surrounding medium. The turnover rate of sodium in the remaining minor fraction of the sodium pool subjected to active transport must be of an order of magnitude comparable to the diffilsion rate of sodium in the thin slices and thereforc faster than the turnover rate of intracellular sodium of striated muscles.
Periodic Variation in the Amount of Semen Yielded at Spontaneous Ejaculations of the Male Rat
Authors: Kihlström J. E. 
Published: December 2008

AbstractJ. E. Kihlström. Periodic variation in the amount of semen yielded at spontaneous ejaculations of the male rat. Acta physiol. scand. 1965. 65, 61–64. — Male rats have been prevented from grooming the penis by means of a stiff girdle, and the spontaneously ejaculated semen has been collected. The amount of semen yielded varies rhythmically with a mean period of 4.4 days.
The Adaptation and the Relation between Discharge Frequency and Current Strength of Cat Lumbosacral Motoneurones Stimulated by Long‐Lasting Injected Currents
Authors: Kernell Daniel 
Published: December 2008

AbstractKernell, D. The adaptation and the relation between discharge frequency and current strength of cat lumbosacral motoneurones stimulated by long‐lasting injected currents. Acta physiol. scand. 1965. 65. 65–73. — Cat lumbosacral motoneurones were stimulated by steady currents injected through the tip of an intracellular micro‐electrode. The results strongly indicate that the majority of undamaged motoneurones are capable of responding to steady currents by long‐lasting and well maintained repetitive discharges. Such discharges from various motoneurones were studied with regard to the adaptation and the slope of the linear relation between discharge frequency and current strength (cf. Granit, Kernell and Shortess 1963 a, b). Measurements were also made of the lowest current strength (in units of rheobase) which was needed for eliciting a steady repetitive discharge. None of these characteristics relating to repetitive firing were found to be correlated with the duration of afterhyperpolarization, the latter being measured by single spike discharges (generally antidromic). The results have been discussed also with reference to earlier findings concerning tonic and phasic repetitive firing of motoneurones stimulated by muscle stretch.
The Limits of Firing Frequency in Cat Lumbosacral Motoneurones Possessing Different Time Course of Afterhyperpolarization
Authors: Kernell Daniel 
Published: December 2008

AbstractKernell, D. The limits of firing frequency in cat lumbosacral motoneurones possessing different time course of after hyperpolarization. Acta physiol. scand. 1965. 65, 87–100. — Long‐lasting repetitive discharges were set up in cat lumbosacral motoneurones by steady currents injected through the tip of an intracellular micro‐electrode. The upper and lower limits of discharge frequency of the various motoneurones were significantly correlated with the time course of their afterhyperpolarization the latter being measured from single spike discharges (generally antidromic). From previous work it is known that the relation between discharge frequency and current strength (the “f‐I relation”) is linear over a certain range from the minimal firing rate and upwards (Granit, Kernell and Shortess 1963, Kernell 1965 b). In the present paper it was shown that the maximal discharge frequency within this linear part of the f‐I relation was also significantly correlated with the time course of afterhyperpolarization. The findings are discussed with regard to problems of regulation of muscle tension by repetitive firing on the part of the motoneurones.
The Distribution in the Mammal Body of F18 and P32 from Double‐Labelled Na2PO3F
Authors: Ericsson Yngve , Hammarström Lars 
Published: December 2008

AbstractEricsson, Y. and L. Hammarström. The distribution in the mammal body of F18and P32 forn double‐labelled Na2PO3F. Acta physiol. scand. 1965.65. 126–137. — Autoradiographic and quantitative investigations with F18, P32‐labelled Na2PO3F were performed on mice and rats in order to study the fate of the monofluorophosphate ion in the mammal body. Comparisons were made with the distribution of F18 as fluoride ions and P32 as orthophosphate ions. Intravenous injection of the double‐labelled POF ion gave strikingly high concentrations of F18 in the intestinal lumen and of P32 in the intestinal wall. A comparatively high concentration of F18 was found in the liver following the ingestion as the PO3F ion. Fluorine ingested as the monofluorophosphate ion did not pass the placenta to any greater extent than when given as the fluoride ion. The indications of these data for further studies of the site and mechanism of splitting and toxicity of monofluorophosphate are discussed.
The Effect of Ethyl Alcohol on Non‐Gustatory Receptors of the Tongue of the Cat
Authors: Hellekant Göran 
Published: December 2008

AbstractHellekant, G. The effect of ethyl alcohol on non‐gustatory receptors of the tongue of the cat. Acta physiol. scand. 1965. 65. 243–250. — Recordings were made of the response in the trigeminal part of the lingual nerve of the cat to the application on the tongue of alcohol, gustatory, thermal and mechanical stimuli. The summated response to alcohol revealed a slowly increasing dischargc after a latency of a few sec. The magnitude of the response increased with increasing alcohol concentrations and attained a maximum at 4 to 5 M alcohol then decreased at higher concentrations. The response of single lingual nerve fibres was also recorded. None of the fibres investigated responded to NaCl, acetic acid or quinine. All fibres responding to alcohol responded also to cooling and mechanical stimulation. The threshold alcohol concentration in the majority of these fibres was about 2.5 M. These fibres displayed a very regular discharge which reached an average maximum frequency of 38 imp/sec at 4.1 M alcohol. A reversible paralysis of the receptors was usually observed at alcohol concentrations of 4.1 M or higher. The conduction velocities of these fibres ranged from 5.7 to 18.0 m/sec. Alcohol did not stimulate myelinated mechanoceptive fibres which responded selectively to light or deep pressure on the tongue (specific mechanoceptive fibres) nor did alcohol stimulate myelinated fibres which only responded to high threshold mechanical or thermal stimulation (specific nociceptive fibres).