bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ventilation at Transition from Rest to Exercise
Authors: Asmussen By Erling 
Published: December 2008

AbstractAsmussen., E. Ventilation at transition from rest to exercise. Acta physiol. scand. 1973. 89. 68–78.The “fast neurogenic component” of the increase in ventilation taking place at the transition from rest to exercise was studied by a breath‐to‐breath analysis of VE. AND PACO2 The questions investigated were: 1) Is the “fast neurogenic component” correlated to the intensity of the exercise: 2) Is it due to a specific work stimulus to the respiratory center, or caused by an increased sensitivity to existing chemical stimuli? 3) Is it related to movements or to the mechanical tensions in the working muscles? The results showed: 1) There is a rough correlation between the “fast neurogenic component” and the power of the bicycle‐work performed. 2) If the chemical stimuli, expressed by PACO2 AND PAo2, are eliminated by voluntary hyperventilation in pure oxygen, the “fast neurogenic component” disappears. With one or both of these stimuli present, exercise augments their effect. 3) Transition from rest to static exercise (no movements) is not accompanied by a “fast neurogenic component”. Rhythmic movements cause a rapid increase in VE, related to the frequency of movement. Sudden loacling of the bicycle during no‐load pedalling causes a relatively slower further increase in ventilation, apparently independent of the force exerted on the pedals, but related to the power of work. It is suggested that some metabolic factor in the working muscles is responsible for this part of the “fast neurogenic component”.
The Count of Mast Cells, Tissue Eosinophils, and Epithelial Mitoses of Rat Gastrointestinal Mucosa after Aspirin Treatment
Authors: RÄSÄNEN Toimi , Taskinen Eero 
Published: December 2008

AbstractRasanen, T. AND E. Taskinen. The count of mast cells, tissue eosinophils, and epithelial mitoses of rat gastrointestinal mucosa after aspirin treatment. Acta, physiol. scand. 1973.89. 182–186.Mucosal mast cells, tissue eosinophils and epithelial mitoses were counted in the gastrointestinal tract of rats given 1, 3 and 5 times 10 nig of aspirin in 5 ml of water at 12 h intervals by cannulation into the stomach. The mast cell count of the gastric and duodenal mucosa ot rats receiving aspirin fell sharply. No significant change was observed in tissue eosinophilia. The mitotic count in the epithelium of stomach declined clearly, but no decrease occurred in the mitoses of the epithelial cells in the mucosa of the duodenum, jejunum and colon. The results seem to indicate that the injurious action of aspirin is transmitted so that the gastric mucosal mast cells possibly participate in it directly: the heparin contained in the mast cell granules inhibits in the phase of liberation the mitotic activity, especially in the gastric epithelium, and the blood coagulation mechanism locally. The histamine and liliydroxy‐tryptamine liberation associated with the release of heparin results in the stimulation of secretion and in vascular reactions of the gastric mucosa.
Growth Hormone and Cortisol Secretion in Man
Authors: Laisi U. , Leisti S. , Leppaluoto J. , Lumio J. , Partanen J. , Virkkunen P. 
Published: December 2008

AbstractLaisi, U., S. Leisti, J. Leppäluoto, J. Lumio, J. Partanenand P. Virkkunen. Growth hormone and Cortisol secretion in man. Acta physiol. scand. 1973. 89. 192–197.In 4 healthy resting males blood was collected through indwelled catheters at 1–3 min intervals and EEG recorded in a sound‐shielded anechoic environment for 30 min (expt. 1). The iminunorcactive plasma growth hormone was at high concentration (10–33 ng/ml) and was secreted in 3 significant bursts in one subject, but was low (0–4 ng/ml) in 3 other subjects. The plasma Cortisol, measured by a fluorometric method, was at low and constant level (mean ±S.D. = 8.9±1.5 μg/100 ml). The EEG vigilance fluctuated between wakefulness and real sleep. The plasma growth hormone concentration tended to be high at wakeful stages and low at sleep stages. There was no correlation between vigilance and plasma Cortisol level. In the middle of the following experiment (expt. 2) a painful faradic current was applied to the forearm for 10 s and blood was collected as in expt. 1. The plasma Cortisol level before the painful stimulus was significantly increased (12.3±4.6 /yg/100 nil) and did not change after the stimulus, in spite of the clear increase of vigilance. The high prc‐stimulus level of plasma Cortisol is evidently due to anticipatory mechanisms. We conclude that growth hormone is secreted in bursts which may last as short as 5 min and that the increase of vigilance could trigger the secretion of growth hormone but not that of Cortisol.
The Effect of Reduced Perfusion Pressure and Regional Sympathetic Vasoconstrictor Activation on the Rate of Absorption of85Kr from the Small Intestine of the Cat
Authors: Svanvik Joar 
Published: December 2008

AbstractSvanvik, J.The effect of reduced perfusion pressure and regional sympathetic vasoconstrictor activation on the rate of absorption of85Kr from the small intestine of the cat.Acta physiol. scand. 1973.89.239–248.The absorption from the small intestinal lumen to the intestinal blood stream of an easily diffusable substance,85Kr, was studied in the cat during different hemodynamic conditions. When reducing arterial inflow pressure to the intestine from about 100 to 30 mm Hg the absorption rate was reduced in proportion to the venous outflow although an earlier study demonstrated an almost unchanged villous blood flow during corresponding experimental conditions. Also when raising the venous outflow pressure absorption rate decreased in proportion to venous outflow while during neurogenic reductions of intestinal blood flow the absorption rate was not significantly changed. The results are discussed mainly with regard to the intestinal mucosal hemodynamics and countercurrent exchanger.
Intrarenal Distribution of Glomerular Filtration in Conscious Rats during Isotonic Saline Infusion
Authors: Clausen By Gunnar , Tyssebotn Ingvald 
Published: December 2008

AbstractClausen, G. and I. Tyssebotn. Intrarenal distribution of glomerular filtration in conscious rats during isotonic saline infusion. Acta physiol. scand. 1973. 89. 289–295.Relative individual glomerular filtration rate (gfr) of juxtamedullar (JM) and superficial (S) nephrons was determined in conscious rats by the 14C ferrocyanide technique. Isotonic saline infused at 250 μd/min × 100 g b.w. for about 60 min reduced fractional Na‐reabsorption by 11 % with no significant change in inulin clearance. The S gfr averaged 90 % of JM gfr both in control and saline loaded animals, but with less scatter in the latter group. Thus the natriuresis produced by acute i.v. isotonic saline loading in conscious rats is not caused by redistribution of filtrate.Extracellular volume expansion Individual nephron filtrate Saline loadingSodium excretion 14C Sodium ferrocyanide
The Distribution of Absorbed 3H‐palmitic Acid in the Intestinal Villi of the Cat during Various Circulatory Conditions
Authors: Jodal Mats , Lundgren Ove 
Published: December 2008

AbstractJodal, M. and O. Lunduren. The distribution of absorbed ‐3H‐palmitic acid in the intestinal villi of the cat during various circulatory conditions. Acta physiol. scand. 1973. 89. 318–326The distribution of absorbed 3H‐palmitic acid within the villous tissue was investigated by determining the amount of radioactivity per unit weight tissue protein in 40 ‐60μm thick tissue slices cut perpendicular to the long axis of the villi. In most experiments a bile solution containing the tracer was incubated in the intestinal lumen for 1 min during in vivo conditions. At “resting” blood flow a steep gradient of radioactivity along the villous length was observed, the highest amount of tracer being found at the tip. This gradient was less steep if the experiments were performed during total intestinal ischemia. The tissue content of “H‐palmitic acid could be markedly decreased by intense vasodilatation or by placing a 7 % albumin solution on the “luminal” surface of the intestinal epithelial cells, after removing the bile solution containing the tracer. The serum albumin, continuously circulating at the “tissue” surface of the epithelial cells, was far less efficient in lowering tissue content of radioactivity. The results are discussed with regard to present concepts of lipid absorption. It is proposed that the results of the present investigation are explained by a “trapping” of the palmitic acid in the intestinal countercurrent exchanger efficiently hindering net blood absorption of the fatty acid.
Studies on the in Vivo Absorption of Butyric Acid in the Small Intestine of the Cat
Authors: Jodal Mats , Lundgren Ove 
Published: December 2008

AbstractJodal, M. and O. Lundgren. Studies on the in vivo absorption of butyric acid in the small intestine of the cat. Acta physiol. scand. 1973. 89. 327–333.The effect of the intestinal countercurrent exchanger on the absorption of short chain fatty acids (SFA; 14C‐butyric and 3H‐propionic acid) was studied in vivo by autoradiography and by using a technique which allowed determination of the tracer concentration along the villous length. A modest concentration gradient from villous tip to villous base was found at “resting” blood flow, the gradient being abolished by maximal vasodilatation or by intestinal ischemia. Furthermore, the tissue content of SFA was largely uneffected by changes in intestinal blood flow. The observations suggest that SFA are far less effected by the countercurrent exchanger than long chain fatty acids. No evidence was provided for the existence of an “active” absorptive mechanism of SFA.
Effect of Body Temperature on Steady State Ventilation and Metabolism in Exercise
Authors: Petersen Ebbe Strange , Vejby‐Christensen Hans 
Published: December 2008

AbstractPetersen, E. S. and H. Vejby‐Christensen. Effect of body temperature on steady state ventilation and metabolism in exercise. Acta physiol. scand. 1073. 89. 342–351.Four healthy subjects were studied at rest and during steady slate of work at normal room and body temperature, and at elevated body temperature (38.5o C) in a climatic chamber. Ventilation, oxygen uptake, carbon dioxide elimination, heart rate, and blood lactate and pyruvate concentrations were measured. At equal work loads ventilation was not different, although respiratory rate was consistently higher and tidal volume lower at elevated temperature. Oxygen uptake was lower, and the ventilatory equivalent therefore higher in hyperthermia than in normothermia. Blood lactate concentration was higher both at rest and at all work loads indicating an increased anaerobic energy yield in hyperthermia. The study indicates the existence of a temperature threshold near 38o C, above which a relative hyperventilation is seen. The observed hyperventilation is hardly caused by changes in the [H+]‐stimulus, and it is suggested that hyperthermia per se or through interaction with other stimuli might constitute the additional ventilatory drive.
Thyroid Function Studies in Normal and Gold‐Exposed Rabbits Using 125I
Authors: Carlson Loren D. , Roohk H. Vernon , Wilson Ove 
Published: December 2008

AbstractCarlson, L. D., H. V. Roohk and O. Wilson. Thyroid function studies in normal and cold‐exposed rabbits using 125I. Acta physiol. scand. 1973. 89. 359–373.Normal uptake and retention of 125I in thyroid was measured for 2–17 weeks in rabbits, and the effect of TSH, T4, acute and extended cold exposure was studied. There were marked interindividual variations in maximum uptake (mean 7 %, range 2.5–18 %), in time to peak (12–72 h), in the slope of the retention curve, and in changes in release rate. Repeated doses gave different maximum uptakes, but time to peak and form of retention curve remained essentially the same for each animal. The mean biological half‐life for a 35‐day period was 12 days for 8 rabbits; the initial half‐life of around 9 days for the 1st week gradually increased to around 16 days during the last 3 weeks. This change suggests a shift of the labelled iodine into thyroidal compartments with slower turnover rates. Analysis of the multiexponential slope showed that the release phases for all rabbit were satisfactorily represented operationally by two exponentials. The mean values for these corresponded to biological half‐lives of 6.4 and 21.1 days. Neither acute and more severe (‐3o and 6o C for 50 h) nor moderate, extended cold (9–10o C for 7–16 days) had the slightest influence on the loss of radioiodine from the thyroid, which nevertheless responded to small doses of TSH.
The Influence of Mechanical Factors on the Response Characteristics of the Frog Muscle Spindle
Authors: Husmark Ivan 
Published: December 2008

AbstractHusmark, I. The influence of mechanical factors on the response characteristics of the frog muscle spindle. Acta physiol. scand 1973. 89. 395–405.The impulse response of the muscle spindle in situ was related to lengthening and tension of the whole muscle during stretch. The results were compared with the impulse response as related to lengthening and tension ohtained from stretches of the isolated encapsulated sensory region (isolated spindle). The aim was to find out if the force‐transmitting structures distorted the stretch stimulus and also to see if the adaptation of the spindle in situ was causally related to the extrafusal tension changes. The results indicate that during stretch the extra‐ and intrafusal fibres develop tension changes, which have the same general characteristics and which are related to the impulse response in a regular way. In some spindles the impulse response did not reflect the general tension of the muscle. This fact lends support to the hypothesis that most of the mechanical deformation of the sensory endings as revealed by the impulse responses is produced by the lengthening of the intrafusal fibres. Furthermore, only a small part of the adaptive decline of the response can be ascribed to the extrafusal tissue tension.
Vagal Relaxation of the Stomach Induced from the Gastric Antrum
Authors: Abrahamsson Hasse 
Published: December 2008

AbstractAbrahamsson, H.Vagal relaxation of the stomach induced from the gastric antrum.Acta physiol scand. 1973.89.406–414.The effect of mechanical stimulation of the gastric antrum on gastric (corpus‐fundus) motility was studied in anesthetized cats. Antral distension elicited a pronounced corpus‐fundus relaxation which was not blocked by atropine, guanethidine or by cervical spinal cord transection but was abolished by blockade of the vagal nerves. The “threshold stimulus” for eliciting the reflex response was an antral distension pressure between 5 and 10 cm H2O. Stepwise increases of antral distension produced correspondingly increased corpus‐fundus relaxations. A steady antral distension could keep the corpus‐fundus part relaxed for at least 10 min. La. infusion of acetylcholine to the antrum produced antral contractions followed by a marked corpus‐fundus relaxation which persisted after guanetnidine. Electric afferent stimulation of antral nerve branches elicited a gastric relaxation similar to the corpus‐fundus response to antral distension.‐It is concluded that activation of slowly adapting “tension receptors”, located in the antral gastric wall and with vagal afferents, elicits gastric relaxation by a reflex activation of the vagal non‐adrenergic rclaxatory fibres to the stomach. These reflex mechanisms are suggested to be involved in the control of gastric reservoir function (receptive relaxation) and gastric emptying. Some effects of vagotomy on gastric motility are discussed in relation to the present findings.
Effect of Acute Exposure to Cold on Blood Thyrotrophin (TSH) and Corticosterone Concentrations in the Rabbit
Authors: Leppäluoto J. , Lybeck H. , Ranta T. , Virkkunen P. 
Published: December 2008

AbstractLeppäluoto, J., H. Lybeck, T. Ranta and P. Virkkunen. Effect of acute exposure to cold on blood thyrotrophin (TSH) and corticosterone concentrations in the rabbit. Acta physiol. scand. 1973. 89. 423–428.Rabbits were exposed to various degrees of cold and plasma TSH concentration was measured by the McKenzie bioassay method (McKenzie 1958) and plasma corticosterone by a fluoro‐metric method. After the transfer of 19 rabbits to a cold room (10o C) no consistent change (p > 0.05) in the plasma TSH level could be seen up to 3 h, whereas the plasma corticosterone level rose transiently from 6.8 to 15.8 μg/100 ml (p<0.01) at 1 h but then fell to the initial level. After immersion of anesthetized rabbits (18 cases) in ice‐cold water for 10 min, the colonic temperature fell from 38 to 30o C. By 2 h plasma TSH levels were again unchanged (p > 0.05) and plasma corticosterone levels had risen from 5.9 to 27.4 μg/100 ml (p < 0.001, 10 cases), or were unchanged (p > 0.05) but high i nanimals pretreated with stereotactically around the preoptic area provoked a decrease in hypothalamic temperature by 3o C (8 cases), while plasma TSH fell to an undetectable level adn corticosterone rose from 18.7 to 26.2 (p < 0.05) μg/100 ml. We conclude that in the rabbit the hypothalamus is refractory to cold stimulus, possibly through a mechanism associated with the secretion of ACTH.
Ionic Fluxes in the Rat Portal Vein and the Applicability of the Goldman Equation in Predicting the Membrane Potential from Flux Data
Authors: Wahlström Bo A. 
Published: December 2008

AbstractWahlstrom, B. A. Ionic fluxes in the rat portal vein and the applicability of the Goldman equation in predicting the membrane potential from flux data. Acta physiol. scand. 1973. 89. 436–448.The sodium, potassium and chloride effluxes from the rat portal vein were measured using radioactive tracer ions. It was found that the sodium efflux attributable to an intracellular compartment was very slow, with a rate constant of 4.66×10‐4 s‐1, and the corresponding intracellular sodium only 3.0 mmol/kg wetweight. The intracellular potassium exchanged with a rate constant of 2.15×10‐4 s‐1 and contained 45.5 mmol/kg wetweight. The intracellular chloride content was 14.7 mmol/kg wetweight, exchanging with a rate constant of 10.55 × 10‐4 s‐1. From these data the permeabilities of Na, K and CI were calculated to 0.130, 3.81 and 3.11 ×10‐8 cms‐1 respectively. The relative permeabilities PK: PNa: PC1 were 1: 0.034: 0.816, and from these values the Goldman equation predicted a membrane potential of ‐42.3 mV. The actual membrane potential, measured by glass microelectrodes, was ‐ 45 mV. It was concluded that the membrane potential in the rat portal vein in normal solution can be predicted from the permeabilities and distribution of K and CI, while Na plays an insignificant part.
Contraction Properties of Cat Facial Muscles
Authors: Lindquist By Christer 
Published: December 2008

AbstractThe contraction properties of some facial muscles of the cat have been investigated. The contraction time of a maximal isometric twitch is 8.5 ms for the orbicularis oculi. 24 ins for the depressor conchae and 33 ms for the orbicularis oris. It is suggested that a slower decay of the active state may be one factor explaining the longer contraction time of the orbicularis oris as compared to the orbicularis oculi. The duration of a maximal compound action potential is also longer for the orbicularis oris than for the orbicularis oculi (8.5 and 2.8 ms respectively). Muscle length is more critical for the twitch amplitude of the orbicularis oculi than for the orbicularis oris. Summation of individual twitches occurs at a stimulus frequency of minimum 20–22 Hz for the orbicularis oculi and at 10–12 Hz for the orbicularis oris. Apparent fusion occurs at 100 Hz for the orbicularis oculi and at 60 Hz for the orbicularis oris. The rate of tension development increases for both muscles with stimulus frequencies up to 200 Hz. Average tetanus/twitch ratios are 4.5 for the orbicularis oris and 7.0 for the orbicularis oculi.
Histochemical Fiber Composition of Some Facial Muscles in the Cat in Relation to their Contraction Properties
Authors: Edström Lars , Lindquist Christer 
Published: December 2008

AbstractA histochemical analysis has been performed of the activity of myofibrillar ATPase, succinic dehydrogenase. NADH2 tetrazolium reductase and phosphorylase and of the content of glycogen and fat in the orbicularis oculi, orbicularis oris and the depressor conchae muscles in the cat. All three muscles contain fibers with a low activity (type I) and such with a high activity (type II) of myofibrillar ATPase. The type II fibers predominate. In general, the type II fibers of the orbicularis oris have a higher activity of oxidative enzymes than those of the other two muscles. Differences in contraction times in relation to fiber composition are discussed. Stimulation of the orbicularis oculi at 5 Hz causes a contractile fatigue of 22–48 % in a 10 min period, which is related to a depletion of glycogen in muscle fibers with a low activity of succinic dehydrogenase. The orbicularis oris fatigues very little (2–21 %) during such a period and no significant glycogen depletion is seen. This is explained by a higher activity of oxidative enzymes in this muscle.
Electrophysiological Study of the Gustatory Effects of the Sweet Proteins Monellin and Thaumatin in Monkey, Guinea Pig and Rat
Authors: Brouwer J. N. , Hellekant G. , Kasahara Y. , Wel H. van der , Zotterman Y. 
Published: December 2008

AbstractThe afferent activity of the facial portion of the chorda‐lingual nerve, the chorda tympani proper, and the glossopharyngeal nerves was recorded during the application of 0.02 % and 0.005 % solutions of Monellin (2times 10‐5 and 5times 10‐6 M) and Thaumatin (10‐5 and 2.1) × 10 ‐6 M) and of 0.5 M sucrose, 0.3 M NaCl and 0.03 M citric acid, representing the three taste qualities sweet, salt and acid. Monellin and Thaumatin, which give a sweet sensation in man, elicited a significant electrophysiological response in the monkey which showed several characteristics that could be related to psychophysical observations in man. In guinea pig and rat little or no response could be recorded.
Cardiovascular Effects of Blood Borne Material Released from the Gat Small Intestine during Simulated Shock Conditions
Authors: Haglund Ulf , Lundgren Ove 
Published: December 2008

AbstractCardiac performance was studied in the cat during and after a mimicked shock situation in the small intestine (regional hypotension at 35 mm Hg during nervous vasoconstrictor fibre activation). Aortic blood flow was measured with an electromagnetic flow probe around the ascending aorta and, in some experiments, maximal dP/dt of the left ventricle was also followed. Upon restoration of intestinal perfusion pressure after a 2 h “shock” period a rapid reduction of aortic flow occurred due to a decreased stroke volume. Concomitantly maximal dP/dt was reduced in the face of an unchanged central venous pressure and left end diastolic pressure. This decline of cardiac performance could be prevented by substituting, during the first posthypotensive min, the intestinal venous blood with fresh blood from a healthy donor animal. However, when the shed intestinal venous blood was retransfused, a rapid decline of cardiac performance was evident. The reduced cardiac function was accompanied by an unchanged or slightly elevated total peripheral resistance. It is proposed that substances released front the “shocked” intestine cause a rapid and pronounced depression of cardiac function.