bluuebunny/crossref_metadata_2025 huggingface dataset:
Selective Adequate Activation of Large Afferents from Muscle Spindles and Golgi Tendon Organs
Authors: Lundberg A. , Winsbury G.
Published: December 2008

An apparatus has been devised for brief stretching of muscles and a method is described for selective activation of I a and I b afferents. With muscles under light initial tension all I a afferents can be activated by a brief stretch of less than 100 μ without co‐activation of any I b afferents. A brief pull applied during contraction of an initially slack muscle activates I b afferents but not I a afferents. With intracellular recording from motoneurones brief stretches activating only I a fibres were found to evoke monosynaptic excitatory postsynaptic potentials almost indistinguishable from those resulting on stimulation of the muscle nerve.
Functional Organization of the Ventral Spino‐Cerebellar Tract in the Cat
Authors: Oscarsson Olov
Published: December 2008

Ventral spino‐cerebellar tract (VSCT) neurones monosynaptically activated by Golgi tendon organ afferents and with inhibitory action from group II and III muscle afferents, skin and high threshold joint afferents, have been investigated in decerebrate cats. In the decerebrate preparation the inhibitory actions are depressed due to a tonic inhibitory control of the interneurones mediating these actions. It is shown that this control changes the message forwarded by the VSCT neurones from one which has been interpreted as extero‐ceptive or informative of flexion reflex patterns to one which is proprioceptive.

In addition a control system not tonically active in the decerebrate preparation is described. It can be activated by stimulation of the brain stem and the responsible fibres are located in the dorsal part of the lateral funicle. It inhibits the ipsilateral VSCT neurones.
The Determination in Vivo of the Rate of Ciliary Beat in the Trachea
Authors: Dalhamn Tore
Published: December 2008

The rate of ciliary beat in the trachea of live rabbits was recorded by filming at 220 frames per second. The animals were able to breathe through their normal respiratory tracts, by a special connection between the microscope and the trachea. The mean rate from 31 subjects was 1,099 beats per minute, the deviation between the animals 172 beats per minute, and the error of method 40 beats per minute. The rate of beat was correlated to the rectal temperature, but did not show any variation during the two hours the experiments lasted. The method can be used for investigations into the effects of inhaled agents (gases, particles) on the ciliary activity of the trachea.
The Specificity of Afferent Cutaneous C Fibres in Mammals
Authors: Iriuchijima J. , Zotterman Y.
Published: December 2008

By dissecting very fine strands of cutaneous nerves in rats, dogs and cats it has been possible to record spikes from single afferent C fibres when applying different stimuli to the skin. Confirming earlier investigators, records have been obtained of the activity of C fibres which responded specifically to tactile stimulation of the skin and from C fibres which responded rather unspecifically to strong thermal changes in the skin in both directions (± 10dg C) as well as to mechanical stimulation of the skin.

In addition to these fibres a new type of C fibres were found which responded specifically to warming or to cooling the skin to less than 1dg C. These specific “warm” C fibres and specific “cold” C fibres showed in general a behaviour similar to that of δ thermal fibres previously described. They did not respond to touching their receptive field. The skin of the mammals investigated thus possess specific “warm” C fibres as well as specific “cold” C fibres which are reciprocally brought in and out of action when the skin is subjected to even slight temperature changes.
Psychomotor Performance in Man as Affected by High Oxygen Pressure (3 Atmospheres)
Authors: Frankenhaeuser Marianne , Graff‐Lonnevig V. , Hesser C. M.
Published: December 2008

Frankenhaeuser, M., V. Graff‐Lonnevic and C. M. Hesser. Psychomotor Performance in man as affected by high oxygen pressure (3 atmospheres).

Psychomotor performance (simple and choice reaction times and mirror drawing) of 10 subjects during exposure to oxygen at 3 atm was compared with performance under normal air breathing at 1 atm. No statistically significant differences in psychomotor performance under the two conditions could be demonstrated. Nor did performance show any tendency to deteriorate with time within the 30 min period employed. The possible importance of these observations as criteria of concomitant physiological events is discussed.
Different Pools of Catecholamines Stored in the Adrenal Medulla
Authors: Hillarp Nils‐Åke
Published: December 2008

Hillarp, N.‐A. Different pools of catecholamines stored in the adrenal medulla.

The nucleotide content of the adrenal medulla (cow, horse, pig and cat) and its changes post mortem were analyzed by means of ion exchange and paper chromatography. The experiments showed that the catecholamines may exist in excess of the adenosinephosphates, which indicates that a not inconsiderable fraction of the amines cannot be stored together with an equivalent amount of adenosinephosphates in the way found in pure amine granules of high density. Examinations of the intracellular distribution of nucleotides and amines indicated that at least some of these amines do not exist “free” in the cytoplasm but are bound in an unknown way to granules of lower density and apparently of lower stability. The probable existence of different pools of stored amines is discussed.
Intracellular Localization of Dopamine in Cow Intestine
Authors: Bertler ÅKe , Hillarp Nils‐Åke , Rosengren Evald
Published: December 2008

Bertler, Å., N.‐Å. Hillarp and E. Rosengren. Intracellular localization of dopamine in cow intestine.

In previous investigations a certain type of chromaffin cells containing dopamine has been demonstrated to occur in ruminant tissues (Falck, Hillarp and Torp 1959, Bertleret al. 1959). It seemed likely that dopamine in these cells was hold in intracellular particles in a similar manner as noradrenaline and adrenaline in the adrenal medulla (Hillarp, Lagerstedt and Nilson 1953). In this study the intracellular distribution of dopamine in the cow intestine which contains high amounts of this amine, has been studied. Some factors affecting this distribution have also been included.
Inhibitory Effects of Hydrochloric Acid in the Duodenum on Gastrin‐Stimulated Gastric Secretion in Heidenhain Pouch Dogs
Authors: Anderson Sven
Published: December 2008

In Heidenhain pouch dogs with duodenum excluded from the normal gastrointestinal passage, gastric secretion was stimulated by continuous intravenous infusion of a gastrin preparation from hog's antral mucosa. On instillation of hydrochloric acid into the duodenum the secretion was decisively inhibited. This finding was taken to indicate that the activated pH‐sensitive inhibitory mechanism in the duodenum exerts its action directly upon the parietal cells.
Some Observations on the Synthesis and Storage of Catecholamines in the Adrenaline Cells of the Suprarenal Medulla
Authors: Bertler A. , Hillarp N.‐Å. , Rosengren E.
Published: December 2008

The intracellular distribution of dopamine, noradrenaline and adrenaline in rabbit suprarenal glands was examined by differential centrifugation of homog‐enates (0.3 M sucrose) of the medullary tissue. The amines were determined spectrophoto‐fluorimetrically.

Glands from normal animals were found to contain no — or very small — amounts of dopamine and noradrenaline. When the medulla was stimulated to secretion by insulin‐induced hypoglycemia, noradrenaline was rapidly formed. It accumulated in the “large granule” fraction, but largely disappeared together with the adrenaline store on prolonged stimulation. Large amounts of “bound” noradrenaline again accumulated during the recovery phase.

Very large amounts of dopamine and noradrenaline rapidly (within 30 min) appeared after an intravenous injection of L‐dopa (100 mg/kg body wt). The new‐formed amines became rapidly “particle‐bound”. In contrast to dopamine which largely disappeared after some hours the noradrenaline remained in large amounts for at least 24 hours.

A tentative scheme of the intracellular events which occur when the adrenaline cell synthesizes and stores catecholamines is proposed and discussed.
The Retention of Par enter ally Injected Calcium in Rachitic Dogs
Authors: Gran Fredrik C.
Published: December 2008

The calcium and phosphorus balances were studied in two vitamin D free, rachitic dogs, 8 months old, given diets rich in Ca and P for 121 days. In the course of the last 113 days 36.4 g Ca (Ca glucono‐galacto‐gluconate) was injected parenterally. Practically all the injected Ca was retained. The faecal Ca exceeded food Ca by about 80 mg daily; the daily urinary Ca was 20–30 mg. The dogs gained about 20g in body Ca in the period of injections. The plasma Ca level was about 7.8 mg/100 ml and was unaffected by the Ca injections. Inorganic P in serum was about 11.5 mg/100 ml before the injections of Ca were started; following the daily Ca load, serum P was reduced to approximately 4 mg/100 ml. At the end of the experiment one dog Received vitamin D. The result was an increase in plasma Ca to 10.7 mg/100 ml in the course of 48 hours and a simultaneous reduction of the urinary Ca. Thus, vitamin D possibly affects the tubular reabsorption of Ca.
Inhibitory Effects of Hydrochloric Acid in Antrum and Duodenum on Histamine‐Stimulated Gastric Secretion in Pavlov and Heidenhain Pouch Dogs
Authors: Andersson Sven
Published: December 2008

In Pavlov and Heidenhain pouch dogs with excluded antrum and duodenum the effects of HCL instillations into those areas upon histamine‐stimulated gastric secretion were studied. It was found that acidification of the duodenum produced slight and irregular inhibition in some dogs, but no inhibition in others. These findings led the author to suggest that histamine‐stimulated gastric secretion is resistant to duodenal inhibition. Acidification of the antrum had no inhibitory influence on the secretion. No difference in susceptibility to antro‐duodenal inhibition was found between secretions from Pavlov and Heidenhain pouches.
Effect of Ethanol and Hydration on the Urinary Excretion of Adrenaline and Noradrenaline and on the Blood Sugar of Rats
Authors: PERMAN E. S.
Published: December 2008

Perman E. S. Effect of ethanol and hydration on the urinary excretion of adrenaline and noradrenaline and on the blood sugar of rats.

Evidence that ethanol increases the adrenal medullary secretion has previously been obtained from studies of the urinary catecholamine output in man and other studies.‐In rats moderate ethanol doses (2.4‐2.7 g/kg) increased diuresis and noradrenaline excretion in comparison with similarly hydrated controls (6.1–6.8 ml/kg). However, further data suggest that ethanol effects on the catecholamine excretion in the dose‐range 0.7‐3 g/kg are explained by the diuretic action of ethanol. Hydration experiments showed that the noradrenaline excretion increased with rising diuresis. The adrenaline excretion was increased at moderate hydration levels.–Ethanol doses above 4 g/kg produced increased adrenaline output and hyperglycemia, as reported by others, and concomitantly caused major changes in the general condition of the rat. It is suggested that the effect of high ethanol doses on the adrenal medullary secretion is secondary to anoxia, due to hypoventilation.
Transfer of Radioactive Iodide Between Mother and Foetus in the Rabbit
Authors: Crone Monna , Waagø Gudrun
Published: December 2008

Crone M. and G. Waagø. Transfer of radioactive iodide between mother and foetus in the rabbit.

Radioiodide injected subcutaneously into rabbits disappeared more rapidly from the serum of pregnant than non‐pregnant animals. To clarify the cause of this difference the 131I uptake in the embryos was measured and higher values were found than corresponded to simple diffusion between mother and foetus. The radioactivity of the foetal gastric juice increased with time. Its 131I concentration was 13 to 109 times higher than in the foetal serum. The 131I concentration in the foetal gastric juice remained high at a time when the 131I concentration had decreased to a low level in the foetal serum. This was considered to indicate that iodide is actively transported through the foetal gastric mucosa and is accumulated in the foetal gastric juice. Radioiodide was found in a higher concentration in the foetal serum and in an even higher concentration in the foetal part of the placenta than in the maternal serum. A steady state of 131 across the placenta was not obtained as the radioactivity of the maternal serum decreased rapidly. A diffusion delay in the foetus was not sufficient to explain the results, which therefore indicated that iodide is actively transported from the mother to the foetus and is concentrated in the foetal part of the placenta. These conclusions were supported by experiments where 131I was administered in such a way that the radioactivity of the maternal serum increased or was constant.

Perchlorate was shown to inhibit the 131I uptake in the foetus by inhibiting the active transport across the placenta and through the foetal gastric mucosa. The iodide concentration mechanism of the foetal part of the placenta was also inhibited.
Hemodynamic Studies with Differential Pressure Technique
Authors: Porjé I. G. , Rudewald B.
Published: December 2008

Porjé I. G. and B. Rudewald. Hemodynamic studies with differential pressure technique. Acta physiol. scand. 1961. 51. 116–135.

A theoretical analysis of the fluid motion in a circular elastic tube is presented. The formulae for computation of pulsatile flow and other hydro‐dynamic data are discussed. Apparatus and technique for recording differential pressure are, described. Results of studies of the hydrodynamics in a model circulation system show that the theory is valid. For kinematic viscosities ranging from 1–9 cst the differential pressure is in the main unaltered. Original differential pressure records from the ascending aorta in cases with normal aortic valves are presented and their features described. Blood velocity curves computed from such curves are presented. To illustrate the use of the method the effect of the Valsalva manoeuvre and a nitrite (Etrynit, Bofors) upon the aortic blood motion are demonstrated.
Renal Clearance in Dogs with Regard to Variations According to Age and Sex
Authors: ÅSheim Å. , Persson F. , Persson S.
Published: December 2008

Åsneim Å., F. Persson S. PerssonRenal clearance in dogs with regard to variations according to age and sex.

Repeated determinations of renal clearance of inulin and PAH were done in 32 dogs. Statistical analysis showed no variations with age and sex. Repeated determinations of TmPAH were done in 16 dogs. The results indicated that even under standardized conditions TmPHA, is highly varying. Statistical data are presented to show that the so‐called self‐depression begins to occur even at the lowest plasma‐PAH‐concentrations considered necessary for achieving a sufficient tubular load.
Cineangiocardiographic Studies of Puppies and Full‐Grown Dogs
Authors: Gribbe Per , Hirvonen Leo , Peltonen Tuomas
Published: December 2008

Gribbe P., L. Hirvonen T. Peltonen. Cineangiocardiographic studies of puppies and full‐grown dogs.

Cineangiocardiographic studies have been carried out on puppies and full‐grown dogs. The volumes of the left atrium and the left ventricle were calculated using 35‐mm film, exposed at a rate of 48 pictures per second. The stroke volume and residual blood volume were calculated from the volume curves. The stroke volume calculated as a percentage of the end‐diastolic volume was larger for the puppies (77 per cent) than for the full‐grown dogs (60 per cent). In relation to their body weight the stroke volume for the full‐grown animals was 60 per cent lower than that for the puppies. The pulmonary circulation time increased with age. It was shorter in puppies than in full‐grown dogs, both absolutely and in terms of the number of cardiac cycles which it occupied. The prolongation of the pulmonary circulation time with advancing age, when expressed in terms of the number of heart cycles which it occupies, may be mainly due to a decrease of the stroke volume in relation to the body weight.
On the Nervous Regulation of the Biliary System in the Cat
Authors: Pallin Benct , Skoglund Sten
Published: December 2008

Pallin B. and S. SkoglundOn the nervous regulation of the biliary system in the cat.

The nervous regulation of the biliary system was investigated on cats. Stimulation of the vagal nerves was shown to increase the pressure in the gallbladder and the hepatic duct, while stimulation of the splanchnic nerves was found to inhibit the action of the vagal nerves. From these experiments is concluded that the vagal nerves exert a ‘secretory’ action on the biliary system, while the splanchnic nerves inhibit the outflow of bile. The mechanisms underlying the interaction of these facilatatory and inhibitory actions are briefly discussed.
Noradrenaline Release from Isolated Nerve Granules
Authors: Euler U. S. v. , Lishajko F.
Published: December 2008

Euler U. S. V. and F. Lishajko. Noradrenaline release from isolated nerve granules.

Some properties of isolated transmitter granules obtained by high g centrifugation of press juice from bovine splenic nerves have been studied. Of the total noradrenaline present in the press juice 20–35 per cent was recovered in the sediment. The granules are stable for several hours at + 4° C but rapidly lose their noradrenaline on incubation in isotonic neutral media at 37° C. Noradrenaline is rapidly released even at low temperature at pH 4 and below, and by detergents. Hypo‐ and hyperosmotic solutions and freezing and thawing, had a moderate releasing effect. Acetylcholine, nicotine, serotonin and GABA had no detectable effect on the noradrenaline release from the granules. Nerve granules are more sensitive to temperature than adrenal medullary granules but show higher resistance to freezing and thawing and osmotic changes.
Air Flow Patterns and Heat Transfer Within the Respiratory Tract: A new method for experimental studies on models
Authors: Ingelstedt Sven , Toremalm Nils Gunnar
Published: December 2008

Ingelstedt S. and N. G. Toremalm. Air flow patterns and hat transfer within the respiratory tract.

The authors have worked out an experimental method which makes it possible to determine air flow patterns in models of the respiratory tract. The method is based on the close relationship between heat transfer and pressure drop conditions which occur in a tube with a warm inner surface when air is blown or sucked through it. The air temperatures before entering and after leaving a tube of tracheal dimensions are determined and the heat transferred to the passing air is computed. Thus heat is used as a tracer. As a result of friction to flow, an aerodynamic boundary layer is built up. It is stated that the shape of this layer determines the actual degree of heat transfer between the airway mucous membranes and the respired air. The hitherto unknown biological importance of variations in the boundary layer within different parts of the respiratory tract is briefly discussed.
On the Origin of Lithocholic and Ursodeoxycholic Acids in Man: Bile Acids and Steroids 106
Authors: Hellström Kjell , Sjövall Jan
Published: December 2008

Hellström K. and J. Sjövall. On the origin of lithocholic and ursodeoxycholic acids in man.

Chenodeoxycholic acid‐2414 C was given perorally to two healthy persons and intravenously to one patient having a bile fistula. In the normal subjects bile was collected from the duodenum every morning for three days. Only a minor part of the chenodeoxycholic acid had been metabolized. About 3 per cent of the activity recovered from the healthy subjects was present as lithocholic acid. Ursodeoxycholic acid accounted for 2 per cent of the activity in one of these subjects. None of these acids were found in the bile fistula patient. Unidentified labelled compounds more polar than chenodeoxycholic acid were present in all bile samples.
Conduction Rates of Afferent Fibres to the Anterior Tongue of the Dog
Authors: Iriuchijima J. , Zotterman Y.
Published: December 2008

Iriuchijima J. and Y. Zotterman. Conduction rates of afferent fibres to the anterior tongue of the dog.

Rate of conduction and sensory function were studied in single afferent fibres of the chorda tympani and the lingual nerve of the dog. All taste fibres appeared to be medullated fibres (Aδ) conducting at rates from 18 to 2 m/sec. The thermal fibres, “cold” as well as the more rare “warm” fibres responding to slight temperature changes (less than 1 °C) were also A δ fibres. All “touch” fibres so far encountered were found to be medullated A fibres. In addition to these medullated fibres some afferent C fibres were found which responded to heavy pressure as well as to extreme temperatures. These fibres obviously serve nociceptive reactions.
X‐Ray Diffraction Studies on Peripheral Nerve Myelin
Authors: Höglund G. , Ringertz H.
Published: December 2008

Hoglund G. and H. Ringertz. X‐ray diffraction studies on peripheral nerve myelin.

The dimension of the radial repeating unit was measured on peripheral nerve from 15 species belonging to 4 vertebrate classes. In the fishes the dimension was 161 ± 3 Å and in the birds 182 ± 5 Å. In the mammalian and amphibian species the dimensions were in agreement with earlier work (185 ± 3 Å and 171 ± 3 Å, respectively).

Diffraction patterns from brachial plexus nerves of sheep fetuses were obtained from a gestation age of approximately 90 days. Weak lines indicating a lower number of regularly arranged radial repeating units compared to older fetuses were obtained from fetuses between 90 and 105 days gestation age. The diffraction patterns from fetuses older than approximately 105 days gestation age were similar to those from peripheral nerves of adult sheep.
Aspects on the Glucose Metabolism of the Hypothalamus and the Pituitary in Goats
Authors: Larsson B. Anderson S. , Pocchiari F.
Published: December 2008

Andersson B., S. Larsson F. Pocchiari. Aspects on the glucose metabolism of the hypothalamus and the pituitary in goats.

With the aid of 14C‐labelled glucose certain aspects of glucose metabolism have been studied in different parts of the hypothalamus and in the posterior and anterior pituitary. The metabolic pattern of the hypothalamus differs from that of the pituitary. Also within the hypothalamus certain differences exist with regard to the fate of the glucose in the incubation medium. Large amounts of GABA are found in the hypothalamus and the posterior pituitary. Glutamine was formed in all samples studied. In the anterior pituitary, glutamine contributes to about 25 % of all amino acids formed from the radioactive glucose. In the hypothalamus and the posterior pituitary about 10 μg per 25 mg of tissue per hour of the glucose present in the incubation medium was converted into amino acids.

The findings are discussed in relation to previous biochemical and physiological studies on this subject.
Localization of Focal Potentials Evoked in the Red Nucleus and the Ventrolateral Nucleus of the Thalamus by Electrical Stimulation of the Cerebellar Nuclei
Authors: Appelberg Bo
Published: December 2008

The experiments described were performed on cats anesthetized with Nembutal. Electrical stimulation was applied to the cerebellar nuclei with stereo‐tactically guided stimulating electrodes. Focal potentials evoked in the mesencephalon and in the thalamus were recorded with glass or tungsten microelectrodes. The potentials were histologically localized to the red nucleus and the ventrolateral thalamic nucleus. It was found that monosynaptic pathways exist between the interposite nucleus in the cerebellum and the red nucleus on one hand and between the interposite nucleus and the ventrolateral nucleus of the thalamus on the other. No activation of the investigated regions could be obtained by stimulation of the dentate or fastigial cerebellar nuclei.
Respiratory Response to Acute Exercise in Induced Metabolic Acidosis
Authors: Refsum H. E.
Published: December 2008

Ventilation, carbon dioxide output and oxygen uptake were recorded before, during and after a work of 500 kgm in one minute — before and after inducing a marked metabolic acidosis by means of ammonium chloride. While the resting ventilation in the acidotic state was moderately increased, the ventilatory increase due to the exercise was extremely high. The excess carbon dioxide blown off simultaneously, however, was very moderate. The increases of the resting and working ventilations were due to increases in the tidal volumes only. The recovery times of carbon dioxide output and ventilation were markedly increased, while the recovery times of oxygen uptake showed no definite change. The described pattern of respiratory response to acute exercise is often found in patients with cardiac or cardiopulmonary disease.
Phenylalanine and Tyrosine in the Adrenal Medulla
Authors: Hall Gösta , Hillarp Nils‐Åke , Thieme Georg
Published: December 2008

The claim (Fellman 1958, Fellman and Devlin 1958) that large amounts of free phenylalanine are present in the adrenal medulla has been tested using cation exchange and paper chromatographic methods. The concentration of this amino acid was found to be very low (< 20 to 40 μg/g wet wt). Tyrosine — but no m‐tyrosine, phenylserine or 3,4‐dihydroxyphenylalanine (< 20 μg/g) – was detected in small amounts (10 to 20 μg/g). Thus the catecholamine producing cells in the gland do not accumulate free phenylalanine or tyrosine to a level appreciably higher than that in the blood plasma.
Occurrence and Distribution of Catecholamines in the Fish Brain
Authors: Euler U. S. von
Published: December 2008

Relatively high amounts of catecholamines were found in the brains of an elasmo‐branch, Squalus acanthias and a teleost, Gadus callarias. Only small quantities could be demonstrated in the brain of a cyclostome, Myxine glutinosa. Both adrenaline and noradrenaline occurred in the brains of Squalus and of Gadus although noradrenaline was predominant. A characteristic distribution of the catecholamines in the brain of Squalus was observed. The highest amount of noradrenaline was found in the diencephalon, hypothalamus, and hypophysis, while the cerebellum contained only very small quantities.
Studies on the Transfer of Phosphate from Mother to Foetus in the Rabbit
Authors: Fuchs Anna‐Riitta , Fuchs Fritz
Published: December 2008

The transfer of phosphate from mother to foetus was studied in rabbits with radioactive P. As in guinea pigs the inorganic phosphate concentration is higher in the foetal than in the maternal plasma, and the transfer takes place against the gradient. The transfer rates calculated from experiments of 30 min duration did only exceed or approach the rate of foetal P retention when the foetal and placental uptake rates were combined. In an experiment of 120 min duration the foetal uptake alone equalled the foetal retention. The combined foetal and placental uptake rates in experiments of varying duration were relatively constant.

In some of the rabbits gestation was artificially prolonged by daily injections of progesterone. The foetal P concentration increases up to but not beyond term. The placental concentration is fairly constant in the second half of gestation and after term, but goes up when intrauterine foetal death occurs, indicating that the placenta stays alive for some time and continues to take up phosphate. The active transport mechanism in the placenta must be localized to the chorionic cells, probably at their boundary toward the intervillous space, building up in the placenta a phosphate pool, from which the foetus is supplied.
Further Studies on the Effect of Catechol on the Isolated Guinea‐Pig Ileum
Authors: SjÖSTRAND N. O.
Published: December 2008

Catechol in doses of 0.1–2 mg added to the isolated guinea‐pig ileum in a 15 ml bath usually induced a contraction of the strip. Atropine and paralyzing doses of cocaine and hexamethonium abolished this contraction. BOL and phenbenzamine had no effect on contractions due to catechol. Catechol in non‐stimulating doses reduced the inhibition caused by adrenaline and noradrenaline. It is suggested that catechol like nicotine stimulates the gut through the mediation of acetylcholine and stimulation of the intramural ganglia.
Oxygen Uptake and Pulse Rate while Running with Undetermined and Determined Stride Lengths at Different Speeds
Authors: Knuttgen Howard G.
Published: December 2008

Two well‐trained subjects ran to steady‐state on a motor‐driven treadmill at speeds between 9 and 16.5 km/h with undetermined stride lengths and at speeds between 9 and 11.66 km/h with a determined length of stride. Determinations of oxygen uptake and pulse rate were made during steady‐state at each speed. The results indicate that kinetic energy is the predominant factor in running (a nearly rectilinear relationship was obtained between oxygen uptake and velocity to the second power). The increase in pulse rate was nearly rectilinearly related to that of oxygen uptake.
Distribution of Blood in the Arousing Hibernator
Authors: Johansen Kjell
Published: December 2008

The distribution of circulating blood has been studied in the arousing hibernator following the method of fractional distribution of radioactive indicators (Sapirstein 1958). The results indicate a conspicuous differential vasoconstriction of the posterior part of the animal during the most active phase of arousal. The blood flow to skeletal muscle in the front of the arousing animals is more than 16 times greater than in the awake non‐hibernating animals. The perfusion rate to the myocardium is twice as large in the arousing animal. Likewise the lungs, diaphragm, and brown fat show a substantial increase in blood flow. Blood flow to gastrointestinal tissues is greatly reduced in the arousing animals, whereas flow to the skin, liver and thyroid shows insignificant differences.
An Analysis of the Current‐Voltage Relationship in Excitable Nitella Cells
Authors: Teorell Torsten
Published: December 2008

Experiments were performed on cells of the fresh water algae Nitella using “triangular waves” of varying frequencies, i. e. depolarizing‐hyperpolarizing currents with varying, linear slopes. With very low frequencies one obtains “steady state rectification” curves, but with intermediate frequencies instability phenomena are revealed. The experimental findings of “dynamic current‐voltage” characteristics are compared with the theoretical results, which can be predicted from the author's “electrohydraulic” hypothesis for excitability phenomena. It is suggested that electro‐osmotic processes, arising from presence of membrane fixed charges, may play a part in the excitability of Nitella.
The Range of Effect of the Sympathetic Vasodilator Fibres with Regard to Consecutive Sections of the Muscle Vessels
Authors: Folkow Björn , Mellander Stefan , ÖBerg Bengt
Published: December 2008

The effect of the activation of the sympathetic cholinergic vasodilator fibres has been studied by a technique permitting an analysis of the reactions in the pre‐ and postcapillary resistance vessels and the capacitance vessels of a skeletal muscle region. The experiments indicate that the dilator fibres are distributed essentially to the bigger precapillary resistance vessels of the muscles, where they can induce almost maximal dilatation, while it is likely that other consecutive vascular sections more or less completely lack such an innervation. The data do not support the view that the dilator fibres open up non‐nutritional specific ‘shunt vessels’, but the above‐mentioned fibre distribution may in certain experimental situations create a ‘functional shunting’ by causing an uneven distribution of capillary flow. A central excitation of these fibres in alarm situations, such as has been suggested, would thus mean an immediate massive blood flow increase in the skeletal muscles, with little or no regional blood ‘pooling’ or opening up of closed capillaries. However, as soon as the skeletal muscles are brought into action, the local production of vasodilator metabolites will open up precapillary sphincters, allowing the already established big flow to be distributed over the entire capillary network.
Physiological Adjustments to Prolonged Diving in the American Alligator Alligator mississippiensis
Authors: Andersen Harald T.
Published: December 2008

Conspicuous physiological adjustments to experimental submersion have been observed in the natural divers among the birds and the mammals. In order to obtain further information on the phenomena associated with water immersion, and to explore these characteristics in other diving vertebrates, experiments have been carried out on the American alligator, Alligator mississippiensis. The heart rate was found to slow down during diving. The pressure induced in the large arteries by ventricular systole diminished only gradually during diastole, probably due to an increased peripheral resistance resulting from a marked vasoconstriction in certain vascular beds. This thesis was supported by the fact that lactic acid formed in the muscles during diving did not appear in the blood until after emersion, suggesting that the blood flow through the muscles is greatly reduced while the animals dive. The alligator may recover easily from a submergence lasting until the oxygen stores are almost completely depleted. These results indicate that the “diving reflexes” occur in a wide variety of vertebrate divers belonging to different phylogenetic groups. They also support the following conclusions:

The circulatory adjustments, by shutting off the perfusion to certain vascular beds, enable the alligator to make the limited oxygen stores last throughout prolonged periods of submersion.

The animal remains in a state of useful consciousness until the oxygen stores are almost exhausted. This serves to extend the safety 4 margin for prolonged diving and ensure a complete utilization of the oxygen available.
Bilirubin, Alkaline Phosphatase and Transaminases in Blood and Lymph during Biliary Obstruction in the Cat
Authors: Carlsten Arne , Edlund Yngve , Thulesius Olav
Published: December 2008

The mechanism of hyperbilirubinemia and enzyme disturbances in acute biliary stasis have been studied experimentally in the cat. Obstruction of the common bile duct (I) and retrograde infusion of BSP and bilirubin solution (II) into the common bile duct towards the liver at pressures exceeding the maximal secretory level was performed. From these studies the following conclusions may be drawn: (1) In biliary stasis bile products simultaneously reach the blood through the hepatic vein and the liver lymph. The role of the lymphatic pathways to the accumulation of bile products seems to be minimal. (2) The rise in alkaline phosphatase activity in lymph and blood after biliary stasis is only moderate in the cat. (3) After biliary stasis there is a significant increase in transaminase activity in both blood and lymph.
The Effect of Chlorpromazine on the Glucose Metabolism in Different Parts of the Goat Brain
Authors: Larsson S.
Published: December 2008

Small doses of chlorpromazine were given parenterally to adult goats. Different parts of the hypothalamus and of the cerebral and cerebrellar cortici as well as of the posterior and anterior pituitary were then incubated with generally labelled 14C glucose. It was found that the respiratory exchange as well as the 14C lactic acid formation was depressed by the drug in the hypothalamus and in the posterior pituitary. The formation of amino acids from exogenous glucose was also inhibited in the same areas after administration of chlorpromazine. The fate of 14C‐labelled glucose was essentially unaffected by chlorpromazine in the cerebral and cerebellar cortici.
Measurement of the Oxygen Diffusion Coefficient in the Subcutis of Man
Authors: Caligara Franco , Rooth Gösta
Published: December 2008

The subcutaneous tissue is considered a ball which is surrounded by a network of capillaries. By applying general equations for the diffusion of gases a series of equations are evolved. These equations show the importance of the different factors which influence the oxygen supply to the subcutaneous tissue. Some preliminary measurements are done in order to show the validity of these equations, and in order to show how they may be used most conveniently. The increase in tissue oxygen tension when a subject is switched over from breathing air to breathing pure oxygen is measured with a covered Pt electrode. From the resulting curve the oxygen diffusion coefficient is calculated. If the oxygen consumption of the tissue and the intercapillary distance is known the capillary oxygen tension and the blood flow may also be calculated. The results obtained are of the expected order of magnitude.
Studies in Neuromuscular Transmission
Authors: Gamstorp Ingrid , Vinnars Erik
Published: December 2008

The effect of acute potassium intoxication on the neuromuscular transmission was studied in rabbits. The sciatic nerve was stimulated through bipolar electrode pairs and the electrical response of the gastrocnemius muscle was recorded. The stimulus necessary to evoke a maximal response, neuromuscular conduction time, nerve conduction time, amplitude and duration of response, refractory and irresponsive periods were measured as was the response to repeated stimulation at a rate of 3 per second. Hyperpotassemia was produced by i. v. infusion (1/2‐1 1/2 ml per min.) of isotonic solution of potassium chloride over 1/2–3 1/2 hours. The observed changes were: Prolonged neuromuscular conduction time, decreased amplitude and prolonged duration of response, prolonged refractory and irresponsive periods. These findings can be explained by a slowing of depolarization and re‐polarization near, at or distal to the neuromuscular junction. They were not caused by the metabolic acidosis nor by the hyponatremia which in some of the experiments accompanied the hyperpotassemia.
Studies in Neuromuscular Transmission
Authors: Gamstorp Ingrid , Vinnars Erik
Published: December 2008

The influence of changes in pH and the partial pressure of carbon dioxide in arterial blood on the neuromuscular blocking effect of a single dose of tubocurarine or dimethyl tubocurarine was investigated in rabbits. The sciatic nerve was stimulated supramaximally at a rate of 3 per second and the electrical response of the gastrocnemius muscle was recorded; the amplitude of the first and fourth response was measured. During the period of spontaneously subsiding block after a single injection of the blocking agent, a shift in the arterial pH was produced either with or without a change in carbon dioxide tension. An increase of the block during this period was always considered significant but a decrease of the block only if it was followed by a spontaenous increase. The action of tubocurarine increased during acidosis and diminished during alkalosis. This effect was greater during metabolic alkalosis and acidosis, corresponding to a more rapid shift in pH, than during respiratory alkalosis and acidosis, but no qualitative difference was observed. The effect of a shift in pH is explained by changes in the potency of tubocurarine. The action of dimethyl tubocurarine was not influenced by changes in pH or carbon dioxide tension.
Restoration of Vasoconstrictor Effects in Reserpinized Cats1
Authors: Rosell Sune , Sedvall Goran
Published: December 2008

Reserpine completely abolishes the effects of vasoconstrictor nerve stimulation (Burn and Rand 1958, Rosell and Rosen 1961). Dopa, dopamine, noradrenaline and adrenaline infused intra‐arterially 20–24 hours after the administration of reserpine partially restored the responses to stimulation of the sympathetic chain. The responsiveness persisted for at least one hour after termination of dopa, dopamine and noradrenaline infusion. With adrenaline, however, vasoconstrictor responses to sympathetic chain stimulation persisted for only a short period after termination of the infusion. The threshold dose for dopa was 2 mg, for dopamine and noradrenaline 25 μg, and for adrenaline 100 μg.

The data are considered to support the hypothesis of Burn and Rand (1960) that the adrenergic nerve terminals or adjacent tissue in reserpinized animals have the ability to store infused dopamine and noradrenaline. Adrenaline seems to be stored to a much lesser extent. Dopamine is presumably converted to noradrenaline, which is then released when the sympathetic chain is stimulated. The weak restoration of vasoconstrictor responses following infusion of dopa is of interest. The degree of restoration of the vasoconstrictor effects following infusion of noradrenaline is presumably related to the time elapsed between the administration of reserpine and the infusion.
Electrical Signs of the Relation between Caudate Nucleus and Cerebral Cortex in Cats1
Authors: Laursen Arne Mosfeldt
Published: December 2008

Cortico‐caudate and caudato‐cortical relationships were explored in the cat using electrical stimuli and recording with gross and micro‐electrodes. The difference in method from previous studies consisted iii the use of a 14‐lead multilead electrode.
Cardiac Inotropic and Skeletal Muscle Vasomotor Responses to Adrenaline and Noradrenaline, Threshold Doses on Intravenous Infusion
Authors: Rosén Anders
Published: December 2008

In cats under chloralose and urethane anesthesia, the mean threshold dose with standard deviation of intravenously infused adrenaline for a cardiac inotropic response was found to be 0.26 ± 0.12 μg/kg/min. and for a muscle vasodilator response 0.44 ± 0.20 μg/kg/min. The mean threshold dose of noradrenaline for an inotropic response amounted to 0.37 ± 0.14 μg/kg/min. and for a muscle vasoconstrictor response to 1.17 ± 0.45 μg/kg/min. The necessity of caution in estimating the differences in the threshold doses between inotropic and vasomotor responses is emphasized.
So‐called Free Erythrocyte Protoporphyrin and its Possible Role in Hemoglobin Formation
Authors: Eriksen Leif
Published: December 2008

The relations of so‐called free erythrocyte protoporphyrin to the number of reticulocytes in the blood of rabbits made anemic by daily injections of 25 mg phenylhydrazine for 5 days, has been studied. The heme forming capacity of the red cells as related to the number of reticulocytes has also been studied. All the data obtained are compatible with the assumption that the amount of free protoporphyrin is not strictly related to the number of the reticulocytes but to the stage of maturation of these cells. The possible role of free erythrocyte protoporphyrin in hemoglobin formation has also been studied, and it has been shown that the main pool of protoporphyrin is not normally utilized for heme formation. It is suggested that free protoporphyrin, although probably a normal intermediate in heme formation, when formed in excess diffuses out into the soluble part of cytoplasm and becomes unavailable for heme formation. The possibility that the true proto‐type intermediate in heme formation differs chemically from protoporphyrin IX is, however, not excluded. It is suggested that excess formed protoporphyrin may in part be the origin of the so‐called early bile pigment fraction found in mammals.
The Formation of Coproporphyrin III and I by Rabbit Reticulocytes Under Hypoxic Conditions in Vitro
Authors: Eriksen Leif , Eriksen Nora , Haavaldsen Synnöve
Published: December 2008

It has been shown that tetrapyrroles having from 4 to 8 carboxylic groups of both the III and I isomer series are formed by rabbit reticulocytes in vitro under hypoxic conditions. The tetrapyrroles of the III series are rapidly converted into protoporphyrin under aerobic conditions, while the tetrapyrroles of the I series are converted into coproporphyrinogen I. The implications of these findings have been discussed and it is suggested that an 8‐carboxylated openchained tetrapyrrolic intermediate of the I series is normally formed by a deaminase, the so‐called porphobilinogenase, and that this tetrapyrrole is condensed spontaneously into uroporphyrinogen I if this condensation is not hindered by a second enzyme, the so‐called isomerase. The possible effect of the latter is discussed and a scheme for the formation of ringformed tetrapyrroles of both the III and I series has been suggested. It is further suggested that the formation of ringformed tetrapyrroles of the I series is due to inhibition or blockage of the isomerase with spontaneous condensation into uroporphyrinogen I of the openchained tetrapyrrole of the I series formed by the deaminase, uroporphyrinogen I being rapidly converted by the decarboxylases present into coproporphyrinogen I. The accumulation of the latter when the atmosphere is changed into air, shows that the enzymes responsible for the conversion of coproporphyrinogen into protoporphyrin are highly specific and can utilize only coproporphyrinogen III and explains why porphyrins having less than 4 carboxylic groups have been found in nature only as isomers of the III series.
Different RNA Fractions during Cell Growth and Synchronous Division in Mass Cultures of Tetrahymena Pyriformis
Authors: Christensson Erik
Published: December 2008

The cellular divisions in mass cultures of the ciliate Tetrahymena pyriformis GL were synchronized through heat treatment. At all stages of the cell cycle were found two metabolically and chemically distinct classes of RNA fractionated by phenol. The fraction left behind in the phenol was poorer in guanylic acid and incorporated radioactive phosphorus more rapidly than the other that had been released in the phenol aqueous phase. The RNA fractions left behind in phenol decreased during heat treatment but showed a rapid increase prior to division. The RNA of the aqueous phase, on the other hand, rose almost proportionally to the cell size up to division. The RNA fraction released in the aqueous phase was chromatographed on Ecteola cellulose ion‐exhange columns.
Distribution of Extra‐ and Intrathoracic Pressure Variations in Rabbits Exposed to Air Shock Waves
Authors: Clemedson Carl‐Johan , Jönsson Arne
Published: December 2008

Rabbits were exposed directly, and excised rabbit and calf lungs after mounting in a pulse guide system, to high explosive air shock waves in a detonation chamber. The incident shock wave as well as the resulting pressure wave patterns were recorded by means of piezoelectric pressure transducers, simultaneously in the lungs, in the heart ventricles, or in the intercostal musculature of both sides of the thorax in the in vivo experiments, and immediately before and after the passage of the lung in the experiments in the pulse guide system. The velocity of propagation of the main part of a pressure pulse in the lung generally was found to be of the order of 15 to 30 m/sec. The velocity of the same type of pulse through the whole chest of some guinea pigs exposed in the pulse guide was of the same order of magnitude, indicating that the main part of the pulse in this case was transmitted through the lungs and not in the thoracic wall structures, which have a much higher transmission velocity. The very low intrathoracic transmission velocity indicates that in an animal, which is exposed freely to and engulfed by the shock wave, the main resulting pressure wave is not propagated through the thorax from one lung to the other. In this case a very complex relationship exists between the temporal and spatial distribution of the resulting extra‐ and intrathoracic forces.